Computer Graphics

Computer Graphics

Computer graphics is extensive, complex and diversified technology. Computer Graphics is a field of computer science that is concerned with digitally synthesizing and manipulating visual contents. It a technique of manipulate visual and geometric information using computational techniques. Computer graphics refers to the creation, storage and manipulation of pictures and drawings using a digital computer. Computer graphics are pictures that are generated by a computer using different technique. With developments in computing technology interactive computer graphics has become an effective tool for presentation of information in such diverse fields as science, engineering, medicine, business, industry, government, art, entertainment, advertising, education, and training. There is virtually no field in which graphical displays cannot be used to some advantage and that is the basic reason why application of computer graphics is so widespread.

Graphical representation makes the study of anything much more interesting. It is a fact that one picture is worth a thousand words. So quite naturally interfaces empowered with Graphics enhances the communication between the computer and its users. Representation of a huge numbers in the form of a graph or a picture helps in better understanding and interpretation of the characteristics or pattern of the data contained in the set of numbers. Graphic displays also improve understanding complex systems, and visualization of two-dimensional (2D), three-dimensional (3D) objects.

Two major 2D graphic types: Bitmap (Raster) and Vector images.

Raster Graphics

Raster Graphics consist of illustrations created using pixels; Rectangular grid of cells of equal size and each cell has its own color. These cells are also called pixels. Raster graphics are also called bitmaps. Digital photographs are the most common type of raster graphics.

Digital photographs in general are raster graphics. Digital camera, uses a certain number of megapixels. This refers to the number of pixels used for a single picture. A defining characteristic of a raster graphic is that when it’s zoomed in very closely, it start to show the actual pixels.

An important property of a raster graphic is its resolution. Resolution indicates the amount of detail, so a higher resolution means more detail. Higher resolution means more pixels, which is why a larger number of megapixels for a digital camera results in sharper photographs.

Vector graphics

Vector graphics consist of illustrations created using line work. In technical terms, you use points, lines, curves and shapes to create the illustration. Vector graphics are based on vectors, also referred to as paths. One of the key characteristics of a vector graphic is that the line work is sharp, even when zoomed in very closely. In a computer application, the line work is stored as a mathematical formula that describes the exact shape of the line. So when its zoomed in, remains a line.

Photo-realistic illustration that is not actually a photograph, the illustration typically consists of very detailed vector graphic containing hundreds or thousands of lines. Vector graphics are created and edited using illustration software. There are a number of different illustration applications. One of the most widely used ones is Illustrator by Adobe. Others include CorelDraw by the Corel Corporation and the open source applications Inkscape and Xara Xtreme. Vector graphics can be stored in a number of different file formats, including AI, EMF, SVG and MWF.

COBOL & Four Divisions

COBOL

COBOL is a language that was developed specifically for business programming. It actually can be used for a wide range of programs and programming problems, but it is most popular for handling traditional business activities. COBOL excels in accounting systems and related activities such as inventory control, retail sales tracking, contact management, commissions, payroll--the list is almost endless.

It is the most widespread commercial programming language in use today. It is English-like and easy to read. This makes it very popular with nonprogrammers. Financial officers frequently can read a section of a COBOL program and understand what it is doing with figures, without having to rely on programmers to interpret the program for them.

COBOL is a high-level programming language first developed by the CODASYL Committee (Conference on Data Systems Languages) in 1960. Since then, responsibility for developing new COBOL standards has been assumed by the American National Standards Institute (ANSI).

Three ANSI standards for COBOL have been produced: in 1968, 1974 and 1985. A new COBOL standard introducing object-oriented programming to COBOL, is due within the next few years.

The word COBOL is an acronym that stands for COmmon Business Oriented Language. As the expanded acronym indicates, COBOL is designed for developing business, typically file-oriented, applications. It is not designed for writing systems programs. For instance you would not develop an operating system or a compiler using COBOL.

The Four Divisions

At the top of the COBOL hierarchy are the four divisions. These divide the program into distinct structural elements. Although some of the divisions may be omitted, the sequence in which they are specified is fixed, and must follow the order below.

IDENTIFICATION DIVISION.

Contains program information

ENVIRONMENT DIVISION.

Contains environment information

DATA DIVISION.

Contains data descriptions

PROCEDURE DIVISION.

Contains the program algorithms

The IDENTIFICATION DIVISION

The IDENTIFICATION DIVISION supplies information about the program to the programmer and the compiler.

Most entries in the IDENTIFICATION DIVISION are directed at the programmer. The compiler treats them as comments.

The PROGRAM-ID clause is an exception to this rule. Every COBOL program must have a PROGRAM-ID because the name specified after this clause is used by the linker when linking a number of subprograms into one run unit, and by the CALL statement when transferring control to a subprogram.

The IDENTIFICATION DIVISION has the following structure:

IDENTIFICATION DIVISION
PROGRAM-ID. NameOfProgram.
[AUTHOR. YourName.]
other entries here

The keywords - IDENTIFICATION DIVISION - represent the division header, and signal the commencement of the program text.

PROGRAM-ID is a paragraph name that must be specified immediately after the division header.

NameOfProgram is a name devised by the programmer, and must satisfy the rules for user-defined names.

Here's a typical program fragment:

IDENTIFICATION DIVISION. PROGRAM-ID. SequenceProgram. AUTHOR. Amar Deep Gorai.

The ENVIRONMENT DIVISION

The ENVIRONMENT DIVISION is used to describe the environment in which the program will run.

The purpose of the ENVIRONMENT DIVISION is to isolate in one place all aspects of the program that are dependant upon a specific computer, device or encoding sequence.

The idea behind this is to make it easy to change the program when it has to run on a different computer or one with different peripheral devices.

In the ENVIRONMENT DIVISION, aliases are assigned to external devices, files or command sequences. Other environment details, such as the collating sequence, the currency symbol and the decimal point symbol may also be defined here.

The DATA DIVISION

As the name suggests, the DATA DIVISION provides descriptions of the data-items processed by the program.

The DATA DIVISION has two main sections: the FILE SECTION and the WORKING-STORAGE SECTION. Additional sections, such as the LINKAGE SECTION (used in subprograms) and the REPORT SECTION (used in Report Writer based programs) may also be required.

The FILE SECTION is used to describe most of the data that is sent to, or comes from, the computer's peripherals.

The WORKING-STORAGE SECTION is used to describe the general variables used in the program.

The DATA DIVISION has the following structure and syntax:

Below is a sample program fragment -

IDENTIFICATION DIVISION. PROGRAM-ID. SequenceProgram. AUTHOR. Amar Deep Gorai. DATA DIVISION. WORKING-STORAGE SECTION. 01  Num1           PIC 9  VALUE ZEROS. 01  Num2           PIC 9  VALUE ZEROS. 01  Result         PIC 99 VALUE ZEROS.

The PROCEDURE DIVISION

The PROCEDURE DIVISION contains the code used to manipulate the data described in the DATA DIVISION. It is here that the programmer describes his algorithm.

The PROCEDURE DIVISION is hierarchical in structure and consists of sections, paragraphs, sentences and statements.

Only the section is optional. There must be at least one paragraph, sentence and statement in the PROCEDURE DIVISION.

Paragraph and section names in the PROCEDURE DIVISION are chosen by the programmer and must conform to the rules for user-defined names.

Sample Program

IDENTIFICATION DIVISION. PROGRAM-ID. SequenceProgram. AUTHOR. Amar Deep Gorai.                     DATA DIVISION. WORKING-STORAGE SECTION. 01 Num1 PIC 9 VALUE ZEROS. 01 Num2 PIC 9 VALUE ZEROS. 01 Result PIC 99 VALUE ZEROS. PROCEDURE DIVISION. CalculateResult.    ACCEPT Num1.    ACCEPT Num2.    MULTIPLY Num1 BY Num2 GIVING Result.    DISPLAY "Result is = ", Result.    STOP RUN.

Some COBOL compilers require that all the divisions be present in a program while others only require the IDENTIFICATION DIVISION and the PROCEDURE DIVISION. For instance the program shown below is perfectly valid when compiled with the Microfocus NetExpress compiler.

Minimum COBOL program

IDENTIFICATION DIVISION. PROGRAM-ID.  SmallestProgram. PROCEDURE DIVISION. DisplayGreeting.    DISPLAY "Hello world".    STOP RUN.

Authorware

Authorware is a multimedia authoring system (environment, tool) for creating computer-based Wikipedia (Multimedia learning applications). It is a multimedia authoring program designed explicitly for learning. Among Authorware's features is that it enables developers to create sophisticated interactivity without having to write any scripts or do any programming. Authorware also comes with scripting capabilities for developers who want to create even more complex interactivity in Authorware.

Features

• Visual programming language (drag and drop icons to create your application's logical outline, and use menus to add content) 
• Built-in data tracking (built-in variables for student activities)
• Support for all sorts of rich media
• Scriptable

Authorware is particularly well suited to creating electronic educational technology (also called e-learning) content, as it includes highly customizable templates for CBT and WBT, including student assessment tools. Working with these templates, businesses and schools can rapidly assemble multimedia training materials without needing to hire a full-fledged programmer. Intuitively-named dialog boxes take care of input and output. The flow chart model makes the re-use of lesson elements extremely straightforward.

Educational technology

Educational technology is the effective use of technological tools in learning. As a concept, it concerns an array of tools, such as media, machines and networking hardware, as well as considering theoretical perspectives for their effective application. Educational technology is not restricted to high technology. Modern educational technology includes (and is broadly synonymous with) e-learning , instructional technology, information and communication technology (ICT) in education, EdTech, learning technology, multimedia learning, technology-enhanced learning (TEL), computer-based instruction (CBI), computer managed instruction, computer-based training (CBT), computer-assisted instruction or computer-aided instruction (CAI), internet-based training (IBT), flexible learning, web-based training (WBT), online education, virtual education, personal learning environment s, networked learning, virtual learning environments (VLE) (which are also called learning platforms), m-learning , and digital education. These labels have been variously used and understood, and conflate to the broad domain of educational technology and e-learning. These alternative descriptive terms are all more restrictive than "educational technology" in that they individually emphasize a particular digitization approach, component or delivery method.

Digital Video

Digital video is audio/visual in a binary format. Information is presented as a sequence of digital data, rather than in a continuous signal as analog information is.

Digital video comprises a series of orthogonal bitmap digital images displayed in rapid succession at a constant rate. In the context of video these images are called frames. We measure the rate at which frames are displayed in frames per second (FPS).

Since every frame is an orthogonal bitmap digital image it comprises a raster of pixels. If it has a width of W pixels and a height of H pixels we say that the frame size is WxH.

Pixels have only one property, their color. The color of a pixel is represented by a fixed number of bits. The more bits the more subtle variations of colors can be reproduced. This is called the color depth (CD) of the video.

An example video can have a duration (T) of 1 hour (3600sec), a frame size of 640x480 (WxH) at a color depth of 24bits and a frame rate of 25fps. This example video has the following properties:

pixels per frame = 640 * 480 = 307,200
bits per frame = 307,200 * 24 = 7,372,800 = 7.37Mbits
bit rate (BR) = 7.37 * 25 = 184.25Mbits/sec
video size (VS) = 184Mbits/sec * 3600sec = 662,400Mbits = 82,800Mbytes = 82.8Gbytes

Types of Video Formats

Windows Media Video (.wmv)

Developed and controlled by Microsoft. WMV is a generic name of Microsoft's video encoding solutions and doesn't necessarily define the technology what it uses -- since version 7 (WMV7) Microsoft has used its own flavour of MPEG-4 video encoding technology. The only difference between ASF files and WMV or WMA files are the file extensions and the MIME types. The basic internal structure of the files is identical. The change in extensions was made to make it easier for an application to identify the content of a media file. A .wma file extension designates a file containing only audio. A .wmv extension designates a file containing both video and audio.

Advanced Streaming Format (.asf)

D.asf Advanced Streaming Format Developed by Microsoft as a multimedia successor to AVI and other individual media file formats, ASF files can contain up to 7 media types including streaming video. ASF is optimized for network distribution and desktop playback. Currently, Microsoft is shifting to the new video file format WMV (Windows Media Video). eveloped by Microsoft as a multimedia successor to AVI and other individual media file formats, ASF files can contain up to 7 media types including streaming video. ASF is optimized for network distribution and desktop playback. Currently, Microsoft is shifting to the new video file format WMV (Windows Media Video). 

QuickTime movie (.mov)

An industry standard developed as part of an entire multimedia architecture by Apple, the QuickTime movie is an open multimedia format which has multi-platform, multi-browser support. Currently (Apr 2003), QuickTime 6 is the newest version and it incorporates streaming and virtual reality capabilities.

Audio-Video Interleave (Video for Windows) (.avi)

The precursor to ASF, AVI files are limited to audio and video only and are not streamable.

RealMedia (.rm)

RealMedia is an industry leader in streaming video technology and is utilized by many Internet real-time video broadcasting sites. Currently, Real One player 6.0 is available.

Various Programs (.mpg)
MPEG-4 is the latest standard for video compression and file format developed by an industry group.  

Graphics Acceleration

A graphics acceleration is a process of sending and refreshing of images to the display monitor and the computation of special effects common to 2-D and 3-D images. Graphics accelerators speed up the displaying of images on the monitor making it possible to achieve effects not otherwise possible - for example, the presentation of very large images or of interactive games in which images need to change quickly in response to user input. Many new personal computers are now sold with a graphics accelerator built in. The power of a graphics accelerator can be extended further if the personal computer is equipped with the Accelerated Graphics Port ( AGP ), a bus (data path) interface between the computer components involved in image display.

Each graphics accelerator provides an application program interface ( API ). Some support more than one API. Among the most popular API's are the industry standard OpenGL and Microsoft's DirectX and Direct3D.

A type of video adapter that contains its own processor to boost performance levels. These processors are specialized for computing graphical transformations, so they achieve better results than the general-purpose CPU used by the computer. In addition, they free up the computer's CPU to execute other commands while the graphics accelerator is handling graphics computations.

The popularity of graphical applications, and especially multimedia applications, has made graphics accelerators not only a common enhancement, but a necessity. Most computer manufacturers now bundle a graphics accelerator with their mid-range and high-end systems.

Aside from the graphics processor used, the other characteristics that differentiate graphics accelerators are:

• Memory : Graphics accelerators have their own memory, which is reserved for storing graphical representations. The amount of memory determines how much resolution and how many colors can be displayed. Some accelerators use conventional DRAM, but others use a special type of video RAM (VRAM), which enables both the video circuitry and the processor to simultaneously access the memory.
• Bus : Each graphics accelerator is designed for a particular type of video bus. As of 1995, most are designed for the PCI bus.
• Register width: The wider the register, the more data the processor can manipulate with each instruction. 64-bit accelerators are already becoming common, and we can expect 128-bit accelerators in the near future

Sound File Format

A sound file format is a file format for storing audio on a computer. There are several different formats, each with its own benefits and drawbacks. The difference between formats generally has to do with storage space versus sound quality. The processor of a computer typically decodes compressed sounds into a format that can be played by the computer.

The way the audio is compressed and stored is call the codec which determines how small the file size is. Some file types always use a particular codec. For example, ".mp3" files always use the "MPEG Layer-3" codec. Other files like ".wav" and ".dct" files support selectable codecs. For example, a ".wav" file can be encoded with the "PCM", "GSM6.10", "MPEG3" and many other codecs. Be careful not to confuse the file type with the codec - it often surprises people to
know you can have a "MPEG Layer-3" encoded ".wav" file. Some file types just contain the audio. But other file types can
contain additional header information which can contain other information about the file (eg .dct files have information about the sender, priority, notes and other data in the file itself).

Below is a description of audio formats supported by Scratch:

MP3
The most popular audio format, a lossy format playable in almost any device and program. Some open-source programs cannot play it due to patent issues, however.

WAV
The default uncompressed audio format on Windows, also playable in most programs.

Most Common Types of Video Files and Containers

Container and Codecs

A digital video file usually consists of two parts. These two parts are called the “Container” and the “Codec”. The container refers to what the actual file type or extension is, for example: .AVI or .MOV. Now, within each of these containers there is a codec which is like a set of instructions that specifies the specific coding and settings of how the video plays on your player. A few popular codecs you may have seen before are: DV NTSC, DivX, Sony YUV. There are much fewer video file containers than codecs, and each container can have hundreds of codecs within them. Most of the popular computer video software is actually preloaded with several of the most popular and most used codec and container decoders to properly playback popular file formats. Odd or proprietary types of codecs may require downloading specialty made codec packs from external sources in order to play correctly.

A Multitude of Formats

There are literally hundreds of video codecs of video formats. Because there are so many possibilities, we may not be able to convert all video files into some of the less popular or proprietary video formats. There are also some video codecs out there that require expensive licensing that we currently cannot offer. Just like .doc indicates a word file, .mov indicates a QuickTime move file; .wmv stands for windows media video and so forth. Here are the most common video file formats, in alphabetical order:

3GP File Extension (.3gp)

The 3gp format is both an audio and video format that was designed as a multimedia format for transmitting audio and video files between 3G cell phones and the internet. It is most commonly used to capture video from your cell phone and place it online. This format supports both Mac and windows applications and can be commonly played in the following:

•            Apple QuickTime Player

•            RealNetworks RealPlayer

•            VideoLAN VLC media player

•            MPlayer

•            MIKSOFT Mobile 3GP Converter (Windows)

Advances Streaming Format (.asf)

ASF is a subset of the wmv format and was developed by Microsoft. It is intended for streaming and is used to support playback from digital media and HTTP servers, and to support storage devices such as hard disks. It can be compressed using a variety of video codecs. The most common files types that are contained within an ASF file are Windows Media Audio, and Windows Media video.

AVCHD (Advanced Video Codec High Definition)

AVCHD (.mts) is a high end, high-definition (HD) format which was originally developed by Sony and Panasonic for high definition home theaters. It’s not really suitable for sharing due to the excessive file sizes, but the format is becoming more and more popular due to HD camcorders using this format. Video in this format would be best suited as the master copy of your video project and serves as a great piece to edit with. AVCHD is still in its early life as a video format and since it’s still fairly new, compatibility with certain video editing programs may be an issue. Some video editing software applications have begun to support this format but many of can not fully handle it quite yet. Additionally, playback of AVCHD files requires speedy CPUs and a sufficient amount of RAM. That alone makes this format more difficult to work with but, on the other hand, it maintains high quality. As time goes by, it will no doubt become easier to use and be more integrated with editing applications.

.AVI (Audio Video Interlaced)

AVI format is a long-time standard developed by Microsoft and has been around as long as digital video has. AVI files (particularly when uncompressed) tend to be HUGE, way too big for the internet or uploading to someone. AVI is more for the beginning of a video project using it as something to edit off of, not the end. In that sense, it is not really a sharing format. They’ll slide into just about any video editing program and the quality is still high enough to be a master clip. AVI is windows-based and is virtually universal. The problem is, not all AVIs are created equally and you can still run into compatibility issues due to different codecs on the videos. The important thing to know is that whatever streams inside the container (AVI) is not necessarily the same from one AVI video to the next because the codecs used for compression can vary from file to file. This is because AVI is what’s known as a “container format”, which basically means it contains multiple streams of different type data, including a control track and separate video and audio streams.

.FLV (Flash Video Format)

Flash video (FLV) is the single most common sharing format on the web today. You’ll see the .FLV file extension on videos encoded by Adobe Flash software to play within the Adobe Flash Player. Virtually everyone (99%) has the adobe player installed in their browser and so this has fast become the most common online video viewing platform. Almost all the video sharing sites stream video in flash. You can upload formats other than flash, and those sites will convert it into flash for streaming to the end user. Notable users of the Flash Video format include YouTube, Yahoo! Video, MySpace, and many others. Many television news operations are also now using Flash Video on their websites as a way to keep viewers up to date at all times. Most of those sites accept uploads in a handful of formats like QuickTime, mpeg4, or wmv, and then they convert it to flash or MP4 before actually putting it out on the net for viewing. In addition to the nearly universal flash video player, FLV is popular because it gives one of the smallest file sizes after compression yet it retains fairly good quality. This means that the videos load quickly on the internet, and won’t spend a lot of time using up your bandwidth. If you self-host your own videos, you should convert them to flash for greatest compatibility with the highest percentage of Internet viewers. Although FLV’s are the most common format found on the web today, the standard is moving towards the use of using MP4 H.264 files within flash players as it is compatible with both online and mobile (iPhone), not to mention some HTML5 browser support (Safari, Chrome).

.MPEG (Motion Picture Experts Group)

MPEGwas developed by the Motion Picture Experts Group. This international group was established in 1988 to develop standards for digital audio and video formats. However, they’re just one of many groups looking to standardize and develop new technologies for digital video.

MPEG-4 (.MP4)

MPEG-4 is another great sharing format for the internet. It’s a small file size, but looks fairly clean in comparison with other video codecs of the same file size. It’s the video format employed by a growing number of camcorders and cameras and it is highly recommended this day and age. In fact, YouTube actually recommends that users upload using MP4 format. YouTube accepts multiple formats, and then converts them all to .flv or .mp4 in their back-end for distribution. As mentioned earlier, more and more online video publishers are moving to MP4 (with H.264 as the video compression codec) as the standard internet sharing format with use within both Flash players as well as HTML5 and most mobile devices. This is the format that we recommend for online delivery of your media.

.WMV (Windows Media Video)

A .WMV file indicates a windows media video file. Windows Media Video is used for both streaming and downloading content via the Internet. Microsoft’s Windows Media Player, an application bundled with Windows operating systems, is built for WMV files. WMV files are of a pretty small file size, actually one of the smallest. As a result of the low file sizes, the videos are compressed so much they start to lose their quality in a hurry. In fact, I’d say the resolution is pretty crummy in comparison to modern codecs. But a tiny file size can be a real advantage in some situations. If you get an email with an actual video attached instead of just a link to a video, it is probably a wmv file. They are the only ones small enough to attach to an email.

.MOV

.MOV is the file extension used to identify an Apple Quick Time Movie. .MOV is an extremely common sharing format, especially among Mac users. It is considered one of the best looking file formats. While MOV files do look great, the files sizes are extremely big. Due to the fact that QuickTime has not been a Mac-only program for quite some time, QuickTime versions and players exist on almost all PCs. The vast majority of the videos we personally upload to the web are QuickTime format, followed by MPEG4. If you see a video file on your computer labeled MSWMM, be aware that this is a windows movie maker project file and not a video or movie file designed for sharing. MSWMM will only play within Movie Maker. When you want to save your movie to share it, use Movie Maker to convert it into a sharing format, such as .mpeg4 or .wmv. The difference between sharing formats and project file formats confuses many people. No matter what video editing software you use, a project file is designed for working on within the editing program. You must convert the project file to watch it on any other player. Now, what streams inside the container is not necessarily the same from one avi video to the next as the codecs used for compression can vary. At DVD Your Memories, when you opt for a video to hard drive transfer, we give you your video tapes as video files in AVI format.

Real Media Format (.rm)

RealMedia is a format which was created my RealNetworks. It contains both audio and video data and typically used for streaming media files over the internet. Realmedia can play on a wide variety of media players for both Mac and Windows platforms. The real player is the most compatible.

Flash Movie Format (.swf)

The Flash movie format was developed my Macromedia. This format can include text, graphics and animation. In order to play in Web Browsers, they must have the Flash Plug-In Installed. The flash plug in comes preinstalled in the latest version of many popular Web Browsers.

Charged Coupled Device

A charge coupled device (CCD) is an integrated circuit etched onto a silicon surface forming light sensitive elements called pixels. Photons incident on this surface generate charge that can be read by electronics and turned into a digital copy of the light patterns falling on the device. CCDs come in a wide variety of sizes and types and are used in many applications from cell phone cameras to high-end scientific applications.

The function of a CCD can be visualized as an array of buckets(pixels) collecting rainwater (photons). Each bucket in the array is exposed for the same amount of time to the rain. The buckets fill up with a varying amount of water, and the CCD is then read one bucket at a time. This process is initiated by pouring water into the adjacent empty column. The buckets in this column transfer their ‘water’ down to a final pixel where the electronics of the camera read-out this pixel (the computer measuring the bucket) and turn it into a number that can be understood and stored by a computer.

CCDs are sensors used in digital cameras and video cameras to record still and moving images. The CCD captures light and converts it to digital data that is recorded by the camera. For this reason, a CCD is often considered the digital version of film. The quality of an image captured by a CCD depends on the resolution of the sensor. In digital cameras, the resolution is measured in Megapixels (or thousands of or pixels. Therefore, an 8MP digital camera can capture twice as much information as a 4MP camera. The result is a larger photo with more detail.

CCDs in video cameras are usually measured by physical size. For example, most consumer digital cameras use a CCD around 1/6 or 1/5 of an inch in size. More expensive cameras may have CCDs 1/3 of an inch in size or larger. The larger the sensor, the more light it can capture, meaning it will produce better video in low light settings. Professional digital video cameras often have three sensors, referred to as "3CCD," which use separate CCDs for capturing red, green, and blue hues.

HTML

What is HTML?

Hypertext Markup Language (HTML) is a syntax used to format a text document on the web. These documents are interpreted by web browsers such as Internet Explorer and Netscape Navigator.

HTML can be created as standard ASCII text with "tags" included to pass on extra information about character formatting and page layout to a web browser. The fact that HTML is, in essence, ASCII text is what makes it so universally compatible. This fact also makes it easy to edit: almost all computers are equipped with a text editor that can be used to edit HTML.

What are Tags?

Tags are what we use to structure an HTML page. Tags start with a '<', then the command, and end with a '>'. For example, the center tag is '<center>'. To stop centering something, we need an ending, or closing tag. Closing tags look exactly like opening tags, except after the first '<' there is a '/'. In other words, the closing tag for center is '</center>'.

HTML Structure

An HTML document has a definite structure that must be specified to the browser. The HTML's beginning and end must be defined, as well as the document's HEAD (which contains information for the browser that does not appear in the browser's main window) and its BODY (which contains the text that will appear in the browser's main window). The use and order of tags that define the HTML structure are described below.

<html>                      Marks the beginning of your HTML
  <head>                  Begins the heading section of an HTML document
    <title> ... </title>Gives an HTML document a title that appears on the browser menu bar, also will appear on search engines or bookmarks referencing your site (must appear between the <HEAD> ... </HEAD> tags; should be straight text, no tags
  </head>                  Defines the end of the heading
  <body>                    Defines the body of an HTML document (text contained within the <BODY> … </BODY> tags appears in the main browser window). Can be used with "BGCOLOR", "TEXT", "LINK", and "VLINK" attributes
</html>                   Defines the end of your HTML document.

Six Advantages of Cloud Computing in Education

Cloud computing entails using a network of remote servers hosted on the internet as opposed to a local server. This helps cut IT costs as well as simplifies content management processes for schools and educational systems.

Advantages that would be especially useful for both students and educators:

Back Up: An important function of the Cloud is that it automatically saves content, making it impossible to lose or delete any valuable material. This means that even if a computer crashes, all documents and content will remain safe, saved, and accessible in the cloud.

Storage: The Cloud allows its users to store almost all types of content and data including music, documents, eBooks, applications, photos, and much more.

Accessibility: Any data stored in the Cloud can easily be accessed from almost any device including mobile devices such as phones or tablets.

Collaboration: Because the Cloud allows multiple users to work on and edit documents at the same time, it enables effortless sharing and transmission of ideas. With this feature, group projects and or collaborative lesson plans can be optimized for both teachers and students.

Resource and Time Conscious: With the availability of content online, it is no longer necessary for teachers to spend time and resources printing or copying lengthy documents or lesson plans. Now, students are able to access homework assignments, lesson notes, and other materials online.

Assignments: I love that the Cloud allows teachers to post assignments online. Students are able to access these assignments, complete them, and save them in a folder to be reviewed later. This means no wasting time turning in papers at the beginning of class as well as no passing germs around during those pesky flu seasons!

Image File Format

JPG, GIF, TIFF, PNG, BMP. What are they, and how do you choose? These and many other file types are used to encode digital images. The choices are simpler than you might think.

Part of the reason for the plethora of file types is the need for compression. Image files can be quite large, and larger file types mean more disk usage and slower downloads. Compression is a term used to describe ways of cutting the size of the file. Compression schemes can by lossy or lossless.

Another reason for the many file types is that images differ in the number of colors they contain. If an image has few colors, a file type can be designed to exploit this as a way of reducing file size.

Lossy vs. Lossless compression

You will often hear the terms "lossy" and "lossless" compression. A lossless compression algorithm discards no information. It looks for more efficient ways to represent an image, while making no compromises in accuracy. In contrast, lossy algorithms accept some degradation in the image in order to achieve smaller file size.

A lossless algorithm might, for example, look for a recurring pattern in the file, and replace each occurrence with a short abbreviation, thereby cutting the file size. In contrast, a lossy algorithm might store color information at a lower resolution than the image itself, since the eye is not so sensitive to changes in color of a small distance.

Number of Color

Images start with differing numbers of colors in them. The simplest images may contain only two colors, such as black and white, and will need only 1 bit to represent each pixel. Many early PC video cards would support only 16 fixed colors. Later cards would display 256 simultaneously, any of which could be chosen from a pool of 224, or 16 million colors. New cards devote 24 bits to each pixel, and are therefore capable of displaying 224, or 16 million colors without restriction. A few display even more. Since the eye has trouble distinguishing between similar colors, 24 bit or 16 million colors is often called TrueColor.

File Types Explained

TIFF is, in principle, a very flexible format that can be lossless or lossy. The details of the image storage algorithm are included as part of the file. In practice, TIFF is used almost exclusively as a lossless image storage format that uses no compression at all. Most graphics programs that use TIFF do not compression. Consequently, file sizes are quite big. (Sometimes a lossless compression algorithm called LZW is used, but it is not universally supported.)

PNG is also a lossless storage format. However, in contrast with common TIFF usage, it looks for patterns in the image that it can use to compress file size. The compression is exactly reversible, so the image is recovered exactly.

GIF creates a table of up to 256 colors from a pool of 16 million. If the image has fewer than 256 colors, GIF can render the image exactly. When the image contains many colors, software that creates the GIF uses any of several algorithms to approximate the colors in the image with the limited palette of 256 colors available. Better algorithms search the image to find an optimum set of 256 colors. Sometimes GIF uses the nearest color to represent each pixel, and sometimes it uses "error diffusion" to adjust the color of nearby pixels to correct for the error in each pixel.

GIF achieves compression in two ways. First, it reduces the number of colors of color-rich images, thereby reducing the number of bits needed per pixel, as just described. Second, it replaces commonly occurring patterns (especially large areas of uniform color) with a short abbreviation: instead of storing "white, white, white, white, white," it stores "5 white."

Thus, GIF is "lossless" only for images with 256 colors or less. For a rich, true color image, GIF may "lose" 99.998% of the colors.

JPG is optimized for photographs and similar continuous tone images that contain many, many colors. It can achieve astounding compression ratios even while maintaining very high image quality. GIF compression is unkind to such images. JPG works by analyzing images and discarding kinds of information that the eye is least likely to notice. It stores information as 24 bit color. Important: the degree of compression of JPG is adjustable. At moderate compression levels of photographic images, it is very difficult for the eye to discern any difference from the original, even at extreme magnification. Compression factors of more than 20 are often quite acceptable. Better graphics programs, such as Paint Shop Pro and Photoshop, allow you to view the image quality and file size as a function of compression level, so that you can conveniently choose the balance between quality and file size.

RAW is an image output option available on some digital cameras. Though lossless, it is a factor of three of four smaller than TIFF files of the same image. The disadvantage is that there is a different RAW format for each manufacturer, and so you may have to use the manufacturer's software to view the images. (Some graphics applications can read some manufacturer's RAW formats.)

BMP is an uncompressed proprietary format invented by Microsoft. There is really no reason to ever use this format.

PSD, PSP, etc. , are proprietary formats used by graphics programs. Photoshop's files have the PSD extension, while Paint Shop Pro files use PSP. These are the preferred working formats as you edit images in the software, because only the proprietary formats retain all the editing power of the programs. These packages use layers, for example, to build complex images, and layer information may be lost in the nonproprietary formats such as TIFF and JPG. However, be sure to save your end result as a standard TIFF or JPG, or you may not be able to view it in a few years when your software has changed.

What is CAD?

Computer Aided Design (CAD) is simply, design and drafting with the aid of a computer.  Design  is creating a real product from an idea.  Drafting  is the production of the drawings that are used to document a design.  CAD can be used to create 2D or 3D computer models.  A CAD drawing is a file that consists of numeric data in binary form that will be saved onto a disk. 

Why should you use CAD?
Traditional drafting is repetitious and can be inaccurate.  It may be faster to create a simple “rough” sketch by hand but larger more complex drawings with repetitive operations are drawn more efficiently using CAD.  

Why use AutoCAD?
AutoCAD is a computer aided design software developed by Autodesk Inc. AutoCAD was first introduced in 1982.  By the year 2000, it is estimated that there were over 4 million AutoCAD users worldwide.  What this means to you is that many employers are in need of AutoCAD operators.   In addition, learning AutoCAD will give you the basics for learning other CAD packages because many commands, terms and concepts are used universally.

Cloud Computing

Cloud computing has been called the way of the future. It opens doors by making applications and technology more accessible than in previous years. Companies that would normally require enormous amounts of startup capital may only need a fraction of what was previously required to succeed.

Currently, if the company can afford it, then they can have access to the full Microsoft Suite, ERP applications, CRM applications, accounting software, and a host of other applications that will improve productivity within a company.

The past of cloud computing is bright, but the future of cloud computing is even brighter. Here is what you may need to know about trends in cloud computing.

Proactive Application Monitoring

Proactive application monitoring technology is currently available, but predictive technology and software will soon make this more robust and accurate. Companies will be able to foresee disaster and avert it, mitigating damage to their systems. This will prevent downtime and make the company safer.

Technology to Ensure Uptime

Companies need uptime guarantees. With low-power processors, data centers will become more affordable, allowing companies to acquire seven to ten data centers around the world in different time zones and thereby allowing them to guarantee 99.9 percent uptime. This will keep companies from losing money and falling prey to their competitors. In the future, this concern will be near obsolete. Because of this, many small hosting companies like GloboTech Communications are offering cloud services to ensure better uptime, while big players like Hivelocity and Amazon are also leveraging this new technology.

Cloud Computing’s Role in Disaster Recovery and Remote Access

Cloud computing enables and enhances remote access and faster disaster recovery. When companies have an emergency information security strategy with security penetration tests, companies can maintain their competitive edge within their respective industries.

With cloud computing, some companies that didn’t recognize a breach may recover within minutes instead of hours. Losing proprietary data can cripple a company and even cause doors to close. Every company should migrate to cloud computing for this reason.

Cloud Computing Becoming More Robust

Cloud computing is becoming more about “fit and function” than about the “hype” surrounding the new technology. Most companies can benefit from cloud computing, but some companies have suffered failed projects during the migration phase because the technology is still in the developmental stages. Typically, migrations fail because of inaccurate or missing data.

Data accuracy must be ensured to avoid catastrophe or business interruption. Service providers must ensure that the migration of all data occurs without mishap. Technicians can still make configuration mistakes that compromise the safety of company data. In the future, migrations will be seamless, and technology will be more robust.

The Ability to Validate Identities through Trusts

In the future, cloud security systems will be able to validate identities through a “centralized trust.” Identity-based security is thought to be more secure than current forms of security. More people will begin to trust cloud computing when this happens.

Centralized Data is the Future in Cloud Computing

Centralized data is expected in abundance in the future of cloud computing. This allows companies to create huge databases. Patient care can be improved with centralized data in huge databases. Better stock market decisions are also possible. Centralized data is a way of the future.

More Capability

Mobile devices that rely on the cloud will become more powerful and thinner because all applications will be web-based. All mobile devices will store data that resides in the cloud, and designers can add more capability and lower costs of the phone. One example of this concept is Apple’s iCloud.

Hybrid Cloud Computing Increases Efficiency

Hybrid cloud computing is expected to help businesses become more efficient by optimizing business process performance. Businesses are excited about hybrid cloud computing because it enhances internal infrastructure and applications. The ability to scale the strengths of local networks and cloud computing is coveted by designers.

Mobile Optimization for Cloud Services

Mobile commerce is on the rise. Cloud computing applications require fewer resources and are recommended for mobile devices. Accessibility is increased because fewer resources are required. This is why cloud computing is recommended for business and personal applications.

Commodity Hardware

Pundits predict that by 2020, low-cost hardware will make it easier to configure advanced data centers capable of complex algorithms at fast speeds. This will increase uptimes and improve user satisfaction. In fact, some pundits commented that “servers and storage devices will look like replaceable sleds.”

Low-Power Processors

Low power processors are expected to lower the cost of operation in large data centers. Users can expect to reduce electricity bills significantly. Low-power ARM chips will make this possible in the upcoming year. With 64-bit capability, uptake should be accelerated. These low-power ARM chips will be used in conjunction with RISC chips and enterprise software to yield an economical and environmentally-friendly solution.

Faster Interconnects

Cloud computing is still in its infancy stage. By 2020, cloud computing is expected to be a permanent solution in many organizations. Data centers will be automated and will support scalable software architecture.

Cloud Computing Will Help Businesses Optimize Their Investments

Cloud computing can help companies optimize investments and scale operations. In the future, new low-power processors and other chip technology will help businesses operate to their full IT capacity. With more innovation, greater revenue potential is possible. Companies can re-invest in their products and services with higher profit margins. Scaling investments will also lead to greater operational agility.

Efficient business models are also possible with cloud computing. With greater efficiency, companies can bring innovative and superior products to market faster than competitors.

Better Overall Security and Assumed Reliability

Currently, designers are working hard to ensure people that cloud computing is the way of the future. It will be the preferred method of hosting applications, platforms, and services. By 2020, it will no longer be a topic of discussion, and experts will be more concerned with how companies can use big data to solve complex problems with cloud computing than with convincing people of its usefulness.

Data center physical security is just as important as data encryption. While minimum encryption regulations may be increased from the current 256-bit SSL, physical access to data center facilities may require biometric scans in addition to electronic pass. These facilities will also be protected by advanced alarm systems.

In addition to physical security, firewall and VPN technology will be improved to protect data transfer. New firewall policies, although not fully defined, will limit VPN traffic to specific IP addresses and ports. With upgraded firmware, breaches will be less likely to occur.

What is the Future of Cloud Computing?

The future of cloud computing is bright for the companies that implement the technology now. While these are some trends that are expected in the future, the future is not limited to these trends. Remain abreast of the latest developments to help your company maintain a competitive advantage. This will make your company more profitable and productive when it can complete tasks faster and more efficiently than the competition.

Acharya Patanjali - Father of Yoga

The Science of Yoga is one of several unique contributions of India to the world. It seeks to discover and realize the ultimate Reality through yogic practices. Acharya Patanjali, the founder, hailed from the district of Gonda (Ganara) in Uttar Pradesh. He prescribed the control of prana (life breath) as the means to control the body, mind and soul. This subsequently rewards one with good health and inner happiness. Acharya Patanjali's 84 yogic postures effectively enhance the efficiency of the respiratory, circulatory, nervous, digestive and endocrine systems and many other organs of the body. Yoga has eight limbs where Acharya Patanjali shows the attainment of the ultimate bliss of God in samadhi through the disciplines of: yam, niyam, asan, pranayam, pratyahar, dhyan and dharna. The Science of Yoga has gained popularity because of its scientific approach and benefits. Yoga also holds the honored place as one of six philosophies in the Indian philosophical system. Acharya Patanjali will forever be remembered and revered as a pioneer in the science of self-discipline, happiness and self-realization.

Varahamihir - Eminent Astrologer and Astronomera (499-587 CE)

Renowned astrologer and astronomer who was honored with a special decoration and status as one of the nine gems in the court of King Vikramaditya in Avanti (Ujjain). Varahamihir' s book "panchsiddhant" holds a prominent place in the realm of astronomy. He notes that the moon and planets are lustrous not because of their own light but due to sunlight. In the "Bruhad Samhita" and "Bruhad Jatak," he has revealed his discoveries in the domains of geography, constellation, science, botany and animal science. In his treatise on botanical science, Varamihir presents cures for various diseases afflicting plants and trees. The rishi-scientist survives through his unique contributions to the science of astrology and astronomy.

Acharya Sushrut - Father of Plastic Surgery (600 BCE)

A genius who has been glowingly recognized in the annals of medical science. Born to sage Vishwamitra, Acharya Sudhrut details the first ever surgery procedures in "Sushrut Samhita," a unique encyclopedia of surgery. He is venerated as the father of plastic surgery and the science of anesthesia. When surgery was in its infancy in Europe, Sushrut was performing Rhinoplasty (restoration of a damaged nose) and other challenging operations. In the "Sushrut Samhita," he prescribes treatment for twelve types of fractures and six types of dislocations. His details on human embryology are simply amazing. Sushrut used 125 types of surgical instruments including scalpels, lancets, needles, Cathers and rectal speculums; mostly designed from the jaws of animals and birds. He has also described a number of stitching methods; the use of horse's hair as thread and fibers of bark. In the "Sushrut Samhita," and fibers of bark. In the "Sushrut Samhita," he details 300 types of operations. The ancient Indians were the pioneers in amputation, caesarian and cranial surgeries. Acharya Sushrut was a giant in the arena of medical science.

Semaphore

A semaphore is a variable or abstract data type that provides a simple but useful abstraction for controlling access by multiple processes to a common resource in a parallel programming environment.

A useful way to think of a semaphore is as a record of how many units of a particular resource are available, coupled with operations to safely (i.e., without race conditions) adjust that record as units are required or become free, and if necessary wait until a unit of the resource becomes available. Semaphores are a useful tool in the prevention of race conditions; however, their use is by no means a guarantee that a program is free from these problems. Semaphores which allow an arbitrary resource count are called counting semaphores, while semaphores which are restricted to the values 0 and 1 (or locked/unlocked, unavailable/available) are called binary semaphores.

Sleeping barber problem

The problem

The analogy is based upon a hypothetical barber shop with one barber. The barber has one barber chair and a waiting room with a number of chairs in it. When the barber finishes cutting a customer's hair, he dismisses the customer and then goes to the waiting room to see if there are other customers waiting. If there are, he brings one of them back to the chair and cuts his hair. If there are no other customers wai

ting, he returns to his chair and sleeps in it.

Each customer, when he arrives, looks to see what the barber is doing. If the barber is sleeping, then the customer wakes him up and sits in the chair. If the barber is cutting hair, then the customer goes to the waiting room. If there is a free chair in the waiting room, the customer sits in it and waits his turn. If there is no free chair, then the customer leaves. Based on a naïve analysis, the above description should ensure that the shop functions correctly, with the barber cutting the hair of anyone who arrives until there are no more customers, and then sleeping until the next customer arrives. In practice, there are a number of problems that can occur that are illustrative of general scheduling problems.

The problems are all related to the fact that the actions by both the barber and the customer (checking the waiting room, entering the shop, taking a waiting room chair, etc.) all take an unknown amount of time. For example, a customer may arrive and observe that the barber is cutting hair, so he goes to the waiting room. While he is on his way, the barber finishes the haircut he is doing and goes to check the waiting room. Since there is no one there (the customer not having arrived yet), he goes back to his chair and sleeps. The barber is now waiting for a customer and the customer is waiting for the barber. In another example, two customers may arrive at the same time when there happens to be a single seat in the waiting room. They observe that the barber is cutting hair, go to the waiting room, and both attempt to occupy the single chair.

Solution

Many possible solutions are available. The key element of each is a mutex, which ensures that only one of the participants can change state at once. The barber must acquire this mutex exclusion before checking for customers and release it when he begins either to sleep or cut hair. A customer must acquire it before entering the shop and release it once he is sitting in either a waiting room chair or the barber chair. This eliminates both of the problems mentioned in the previous section. A number of semaphores are also required to indicate the state of the system. For example, one might store the number of people in the waiting room.

Implementation

The following Python code guarantees synchronization between barber and customer and is deadlock free, but may lead to starvation of a customer. The functions wait() (originally P, for the Dutch proberen = try) and signal() (originally V, for the Dutch verhogen = raise) are functions provided by the semaphores.

5 characteristics of Cloud Computing

On demand self services

Computer services such as email, applications, network or server service can be provided without requiring human interaction with each service provider. Cloud service providers providing on demand self services include Amazon Web Services (AWS), Microsoft, Google, IBM and Salesforce.com. New York Times and NASDAQ are examples of companies using AWS (NIST). Gartner describes this characteristic as service based.

Broad network access

Cloud Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms such as mobile phones, laptops and PDAs.

Resource pooling

The provider’s computing resources are pooled together to serve multiple consumers using multiple-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand. The resources include among others storage, processing, memory, network bandwidth, virtual machines and email services. The pooling together of the resource builds economies of scale (Gartner).

Rapid elasticity

Cloud services can be rapidly and elastically provisioned, in some cases automatically, to quickly scale out and rapidly released to quickly scale in. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be purchased in any quantity at any time.

Measured service

Cloud computing resource usage can be measured, controlled, and reported providing transparency for both the provider and consumer of the utilized service. Cloud computing services use a metering capability which enables to control and optimise resource use. This implies that just like air time, electricity or municipality water IT services are charged per usage metrics – pay per use. The more you utilize the higher the bill. Just as utility companies sell power to subscribers, and telephone companies sell voice and data services, IT services such as network security management, data center

hosting or even departmental billing can now be easily delivered as a contractual service.

Multi Tenacity

Is the 6th characteristics of cloud computing advocated by the Cloud Security Alliance. It refers to the need for policy-driven enforcement, segmentation, isolation, governance, service levels, and charge back/billing models for different consumer constituencies. Consumers might utilize a public cloud provider’s service offerings or actually be from the same organization, such as different business units rather than distinct organizational entities, but would still share infrastructure.

आर्यभट

Nagarjuna

Aacharya Charak

Acharya Kanad

भास्कराचार्य दुतीय

Microsoft Windows XP

Introduction

There are many new and exciting features at your fingertips in Windows XP. Some of these features are making their debut in Windows XP but they are built off of Windows 98. There are new tools you can use to get the most out of your computer experience, and other technologies that run in the background, making your computer run more efficiently and reliably.

First, what you can't see, Windows XP has great capability in the behind-the-scenes running of your computer. Overall security has been improved. Performance is at an all-time high, allowing you to use more programs and have them run faster than ever. Windows XP is dependable and stable, so you can always rely on the performance and effectiveness of your computer. Best of all, compatibility with other programs is better than ever. Windows XP is designed to make you have less work to do with the least amount of hassle.

Start Menu

Clicking Start displays a menu that lets you easily access the most useful items on your computer. Clicking All Programs opens a list of programs currently installed on your computer. The list of programs on the Start menu is divided into two parts: the programs displayed above the separator line (also known as the pinned items list) and the programs displayed below the separator line (also known as the most frequently used programs list). The programs on the pinned items list remain there and are always available for you to click to start them. You can add programs to the pinned items list.

Programs are added to the most frequently used programs list when you use them. Windows has a default number of programs that are displayed on the most frequently used programs list. When that number of programs is reached, the programs you have not opened recently are replaced by the programs you used last.

• All Programs – The all programs menu holds all of the applications that come with Windows XP or ones that you have installed that are supplied by the university or ones that you have installed yourself.
• My Recent Documents – is a list of the most recent documents that you have worked on.
• Control Panel – NEW! It now has its own menu. Control Panel is full of specialized tools that are used to change the way Windows looks and behaves.
• Help and Support - NEW! The Help and Support Center is your comprehensive resource for tools and information. Use Search, the Index, or the table of contents to gain access to the extensive online Help system.
• Search – NEW! This use to be called Find, this option allows you to search for files and folders on your computer.
• Run – This option allows you to specify a program to run if it does not have an entry in the All Programs Menu
• Turn Off The Computer – NEW! It is the same as the Shutdown option from Windows 98. IT IS VERY IMPORTANT FOR YOU TO USE THIS OPTION BEFORE YOU TURN OFF THE COMPUTER.

The Control Panel

To open Control Panel, click Start and then click Control Panel.

Control Panel is full of specialized tools that are used to change the way Windows looks and behaves. Some of these tools help you adjust settings that make your computer more fun to use. For example, use Mouse to replace standard mouse pointers with animated icons that move on your screen, or use Sounds and Audio Devices to replace standard system sounds with sounds you choose. Other tools help you set up Windows so that your computer is easier to use.

When you first open Control Panel, you will see some of the most commonly used Control Panel items organized by category. To find out more information about an item in Control Panel while in Category view, hold your mouse pointer over the icon or category name and read the text that appears. To open one of these items, click its icon or category name. Some of these items will open to a list of tasks you can perform, as well as a selection of individual Control Panel items. For example, when you click Appearance and Themes, you will see a list of tasks such as Choose a screen saver along with individual Control Panel items. If you open Control Panel and do not see the item you want, click Switch to Classic View.

Display Properties

Windows provides different options for the look of the screens. To get to the display options in Control Panel click on Display then on the Appearance tab. This is the screen that will appear:

• Under Windows and Buttons you can change the look of a Window Box to the XP style (above) or you can select Classic style, which is the style that was used in Windows 98.
• Under Color Scheme you can choose different color for the windows boxes.
• Under Font Size you can choose between small, normal, and large icons.

Mouse Settings

The mouse option can also be found in the Control Panel under Mouse.

Mouse Properties allows you to choose whether you want it as a right-handed or left handed mouse, the double-clicking speed, and also click-lock: which is a NEW! feature. This enables you to highlight or drag without holding down the mouse button. You can choose your pointer, the pointer speed, and the visibility of the pointer. You can choose how many lines you can scroll over when using the mouse.

Setting a Screen Saver

A screen saver is a program that displays moving graphics or words on your screen when you are not working. To choose a screen saver, select Display in the Control Panel then choose the Screen Saver Tab. 

Use the Screen Saver pull down menu to choose a screen saver. If there are settings that you want to change for the screen saver, use the Settings button. The Wait prompt allows you to change the time it takes for the screen saver to appear while the computer is idle.

The Accessories Menu

• Calculator – it can be set for simple or complex math operations.
• Command Prompt - MS-DOS, the acronym for Microsoft Disk Operating System, is an operating system with a command-line interface used on personal computers.
• Notepad – A simple text editor.
• Paint – A paint program for editing pictures.
• Word Pad - A low level word processor.

WordPad

You can use WordPad to create or edit text files that contain formatting or graphics. (Use Notepad for basic text editing or for creating Web pages.) You can add special formatting such as boldface, italic, and underline. WordPad has many features but if you already have a capable word processor (e.g. Microsoft Word) it is recommended that you use that.

• To open WordPad, click Start, point to All Programs, point to Accessories, and then click WordPad.

Paint

Paint is a drawing tool you can use to create black-and-white or color drawings that you can save as bit map (.bmp) files. You can also use Paint to send your drawing in e-mail, set the image as a desktop background, and save image files using different file formats.

• To open Paint, click Start, point to All Programs, point to Accessories, and then click Paint.

Multi-Tasking

One of the most useful features of Windows XP is multi-tasking. Multitasking is the process of running two or more programs at the same time. With this feature you can quickly copy information from one program to another. A NEW! Feature in Windows XP is grouping in multitasking. It groups different documents all from the same program together.

Shortcuts

Shortcuts are icons that can be placed on the desktop or in the Start Menu. They represent programs, folders and files that are on the computer. Since they only represent items, they can be copied, moved and deleted without any harm to the actual program, folder, or file.

To Create a Shortcut on the Desktop:

• Use the right mouse button to click on the desktop (anywhere not in a window), a menu will appear.
• From the New menu choose Shortcut.
• This dialog box will walk you through the process of creating the shortcut. Once you find the file by clicking on the browse button, you can name the folder or file anything you like. If you make a mistake in the previous dialog window click the Back button. Then click Finish and you will see the shortcut on your desktop.

My Computer

In My Computer you can browse through a hierarchy of folders on your computer and all the files and folders in each selected folder.

To start My Computer

You can either double-click on the My Computer icon on your desktop or you can go to the Start Menu and select My Computer.

You can select a number of different views to look at My Computer.

To access any file click on the drive that it is stored on and locate the file.

Changing Your Desktop

To change your desktop, click on the Start Menu, and then the Control Panel, select Display, and then click on the desktop tab.

There are many choices to choose from! Highlight the one you prefer, then click apply, and then click OK. You can also create your own by clicking on the Browse button and locate a picture that you have saved then click apply, then click ok.

When you click on Customize desktop, there are more advanced options such as the look of the icons, and a New! cleanup tool feature for your desktop to make it less cluttered.

Making Your Own Icons

This will allow you to create the icons that appear on your desktop.

• Click on Start, Programs, Accessories, and Paint.
• From the pull down menu bar, click on Image and then select Attributes.
• Enter 32 Pixels in Height and Width. Click Ok.
• A small white box appears. Then create an icon using the Paintbrush or Pencil Tools.
• Select File, Save As. Name the file and click Save.

Replacing the Shortcut on Your Desktop

Replacing the Shortcut allows you to change the standard icons to ones you have created.

• Right-click on the shortcut and choose Properties.
• Click on the Change Icon button.
• Click on Browse and locate the icon you saved.
• Locate the file and highlight it. Click Open. Then click OK.