Notes on ICT

ICT

A complete computer system consists of four parts:

·         Hardware: Hardware represents the physical and tangible components of the

·         Software: Software is a set of electronic instructions consisting of complex codes (Programs) that make the computer perform

·         User: The computer operators are known as

·         Data: Consists of raw facts, which the computer stores and reads in the form of

Functionalities of a computer

Any digital computer carries out five functions in gross terms:

·         Takes data as input.

·         Stores the data/instructions in its memory and use them when required.

·         Processes the data and converts it into useful information.

·         Generates the output

·         Controls all the above four steps.

The following features characterize this electronic machine:

·         Speed	·         Flexibility
·         Accuracy	·         Low cost
·         Storage and Retrieval ·         Reliability	·         Repeated Processing Capabilities

Applications of Computer:

Following list are various applications of computers in today’s arena.

·         Business	·         Health Care
·         Banking	·         Engineering Design
·         Insurance	·         Military
·         Education	·         Communication
·         Marketing	·         Government

Following are the main five generations of computers:

S. No.	Generation & Description
1	First Generation (1946-1959)  – Vacuum tube based
2	Second Generation (1959-1965) –  Transistor based
3	Third Generation (1965-1971) –  Integrated Circuit based
4	Fourth Generation (1971-1980) – VLSI microprocessor based
5	Fifth Generation (1980-onwards) – ULSI microprocessor based

Computer hardware consists of the following components:

1.    CPU (Central Processing Unit): CPU is considered as the brain of the computer. It performs all types of data processing operations, stores data, intermediate results and instructions (program).It controls the operation of all parts of

 

[A] CPU itself has following three components:

·         ALU (Arithmetic Logic Unit): When the control unit encounters an instruction that involves mathematical calculation or decision/logic, it passes the control to the second component, i.e., the arithmetic logic unit (ALU). The ALU includes a group of registers – memory locations built directly into the CPU – that are used to hold data that are being processed by the current

·         Registers: The register is the smallest high-speed storage area in the CPU. All data must be represented in a register before it can be

·         Control Unit: This unit controls the operations of all parts of computer but does not carry out any actual data processing operations

[B] Primary memory consists of mainly two types of memories:

1. Random Access Memory (RAM): RAM is the internal memory of the CPU for storing data, program and program result. It is read/write memory which stores data until the machine is working. As soon as the machine is switched off, data is erased.

RAM is volatile, i.e. data stored in it is lost when we switch off the computer or if there is a power failure. Hence a backup uninterruptible power system (UPS) is often used with computers. RAM is small, both in terms of its physical size and in the amount of data it can hold.

There are mainly three types of RAM available:

·         Dynamic Random Access Memory (DRAM): A type of physical memory used in most personal computers. The term dynamic indicates that the memory must be constantly refreshed2 (reenergized) or it loses its contents. This type of memory is more

·         Static Random Access Memory (SRAM): A type of memory that is faster and less volatile than DRAM, but requires more power and is more expensive. The term static is derived from the fact that it does not need to be refreshed like

·         Synchronous Dynamic Random Access Memory (SDRAM): A type of DRAM that can run at much higher clock

2. Read Only Memory (ROM): The memory from which we can only read but can not write on it . This type of memory is non-volatile. The information is stored permanently in such memories during manufacture. A ROM, stores such instructions that are required to start a computer. This operation is referred to as bootstrap.

There are mainly three types of ROM available:

·         MROM (Masked ROM): The very first ROMs were hard-wired devices that contained a pre-programmed set of data or instructions. These kinds of ROMs are known as masked ROMs which are

·         EPROM (Erasable and Programmable Read Only Memory): The EPROM can be erased by exposing it to ultra-violet light for a duration of up to 40 minutes. Usually, an EPROM eraser achieves this

·         EEPROM (Electrically Erasable and Programmable Read Only Memory): The EEPROM is programmed and erased electrically. It can be erased and reprogrammed about ten thousand times. Both erasing and programming take about 4 to 10 ms (milli second).

Memory

A memory is just like a human brain. It is used to store data and instructions. Computer memory is the storage space in a computer where data is to be processed and instructions required for processing are stored. The memory is divided into a large number of small parts called cells. Each location or cell has a unique address which varies from zero to memory size minus one.

Memory is primarily of three types –

·         Cache Memory: It is a very high-speed semiconductor memory which can speed up CPU. It acts as a buffer between the CPU and main memory.

·         Primary Memory/Main Memory: Primary memory holds only those data and instructions on which computer is currently working. It has limited capacity and data is lost when power is switched off.

·         Secondary Memory: This type of memory is also known as external memory or non-volatile. It is slower than main memory. These are used for storing data/Information permanently.

1.  Secondary Storage (External Storage Devices): Floppy diskettes, hard disk, tapes and optical disks come under the category of external storage devices or ancillary storage devices. These devices are very sensitive to environmental conditions (humidity and temperature) as well as to external magnetic fields and need to be stored.

·         Floppy Disk: Floppy disks are primarily used on PCs. Information on a floppy disk is recorded in the magnetized states of particles of iron oxides evenly placed upon concentric circles known as Tracks.

·         Hard Disk: It is a non-removable enclosed magnetic disk included in most PCs. It contains a stack of metal platters, each coated with iron oxide, that spin on a spindle and the entire unit is encased in a sealed chamber.

·         Magnetic Tape: This is plastic tape, usually made of Mylar that is coated with iron oxide, thereby enabling the introduction (writing); retention (memory) and reading of magnetically recorded information. The best use of tape storage is for data that you do not use very often.

2. Peripherals: Peripheral devices are devices connected to the computer externally. If a peripheral device is disconnected, the computer will still be able to work; only functions performed by this peripheral device will not be available.

Mainly there are following types of peripheral devices:

A. Input Devices (How to tell it what to do): This unit makes a link between user and computer. The input devices translate the information into the form understandable by

1.    Keyboard- The most common and very popular input device which helps in inputting data to the computer.

2.    Mouse- Mouse is the most popular pointing device and cursor-control device having a small palm size box with a round ball at its base which senses the movement of mouse and sends corresponding signals to CPU when the mouse buttons are pressed.

3.    Joy Stick- To move cursor position on a monitor screen. It is mainly used in Computer Aided Designing (CAD) and playing computer games.

4.    Light pen- It is used to select a displayed menu item or draw pictures on the monitor screen.

5.    Track Ball- Mostly used in notebook or laptop computer, instead of a mouse. This is a ball which is half inserted and by moving fingers on ball, pointer can be moved.

6.    Scanner- A scanner allows you to scan printed material and convert it into a file format that may be used within the PC.

7.    Digitizer- It converts analog information into digital form.

8.    Microphone-Microphone is an input device to input sound that is then stored in digital form.

9.    Magnetic Ink Character Recognition (MICR)- MICR input device is generally used in banks because of a large number of checks to be processed every day.

10.  Optical Character Reader (OCR)- OCR scans text optically character by character, converts them into a machine-readable code and stores the text on the system memory.

11.  Bar Code Reader- A device used for reading bar coded data (data in form of light and dark lines). Barcoded data is generally used in labeling goods, numbering the books.

12.  Optical Mark Reader(OMR)- A special type of optical scanner used to recognize the type of mark made by pen or pencil.

B. Output Devices: (How it shows you what it is doing) Output devices translate the computer’s output into the form understandable by

Monitors: Monitors, commonly called as Visual Display Unit (VDU), are the main output device of a computer. It forms images from tiny dots, called pixels that are arranged in a rectangular form. The sharpness of the image depends upon the number of pixels.

There are two kinds of viewing screen used for monitors.

1.    Cathode-Ray Tube (CRT): The CRT display is made up of small picture elements called pixels. The smaller the pixels, the better the image clarity, or resolution

2.    Flat- Panel Display: The flat-panel display refers to a class of video devices that have reduced volume, weight and power requirement in comparison to the

Printer: Printer is an output device, which is used to print information on paper.

1.    Impact Printers: The impact printers print the characters by striking them on the ribbon which is then pressed on the

2.    Non-Impact Printers: Non-impact printers print the characters without using ribbon. These printers print a complete page at a time so they are also called as Page Laser Printers, Inkjet Printers.

Notes:

·         Data: Data can be defined as a representation of facts, concepts or instructions in a formalized manner which should be suitable for communication, interpretation, or processing by human or electronic

·         Information:- Information is organized or classified data which has some meaningful values for the receiver. Information is the processed data on which decisions and actions are

·         Data Processing Cycle: Data processing is the re-structuring or re-ordering of data by people or machine to increase their usefulness and add values for particular Data processing consists of basic steps input, processing and output.

These three steps constitute the data processing cycle.

·         Input -Input data is prepared in some convenient form for processing. The form will depend on the processing machine. For example, when electronic computers are used, the input data could be recorded on any one of several types of input medium, such as magnetic disks, tapes and so on.

·         Processing – In this step input data is changed to produce data in a more useful form. For example, paychecks may be calculated from the time cards, or a summary of sales for the month may be calculated from the sales orders.

·         Output – The result of the proceeding processing step are collected. The particular form of the output data depends on the use of the data. For example, output data may be pay-checks for employees.

Information and communication technology:

• ICT : Meaning, Advantages, Disadvantages and Uses.
• General Abbreviation and Terminology.
• Basics of Internet and E – mailing.

COMPUTER AND ITS MAIN COMPONENTS

A Computer is a General purpose machine, commonly consisting of digital circuitry, that accepts (inputs), stores, manipulates, and generates (outputs) data as numbers, text, graphics, voice, video files, or electrical signals, in accordance with instructions called a program

• Father of the computer – Charles Babbage
• Father of the modern computer – Alan Turing
• Basic Architecture of Computer: John Von Neumann (1947-49)
• First Programmer: Lady Ada Lovelae (1880)
• First Electronic Computer: ENIAC (1946) – J.P. Eckert & J.W. Mauchly
• First computer for the home user introduced – IBM in 1981

Mains Parts of computer

Hardware – Computer hardware is what you can physically touch includes the computer case, monitor, keyboard, and mouse. It also includes all the parts inside the computer case, such as the hard disk drive, motherboard, video card, and many others.

Input Devices – In computing, an input device is a peripheral (piece of computer hardware equipment) used to provide data and control signals to an information processing system such as a computer or information appliance.

Examples: keyboards, mice, scanners, digital cameras and joysticks.

Keyboard – A Keyboard is the most fundamental input device for any computer system. It helps to enter data in computer.

Mouse – A mouse is used to input data by sending a signal to the computer, based on hovering the cursor and selecting with the left mouse button. The left mouse acts as a ‘enter’ button. The right mouse button can be selected and will often pop up a window of choices. The scrolling wheel is used to move the view of the screen up or down. By moving your mouse to a location in a document, on a digital photo or over a choice of music, you can click the left mouse button to place the cursor.

Trackballs – A trackball is an input device used to enter motion data into computers or other electronic devices. It serves the same purpose as a mouse, but is designed with a movable ball on the top, which can be rolled in any direction. Instead of moving the whole device, you simply roll the movable ball on top of the trackball unit with your hand to generate motion input.

Barcode reader – A barcode reader (or barcode scanner) is an electronic device that can read and output printed barcodes to a computer. Like a flatbed scanner, it consists of a light source, a lens and a light sensor translating optical impulses into electrical ones.

Digital camera – a camera which produces digital images that can be stored in a computer and displayed on screen.

Gamepad – a handheld controller for video games.

Joystick – a lever that can be moved in several directions to control the movement of an image on a computer or similar display screen. It mainly used in playing games.

Microphone – an instrument for converting sound waves into electrical energy variations which may then be amplified, transmitted, or recorded.

Scanner – a device that scans documents and converts them into digital data.

Webcam – a video camera connected to a computer, allowing its images to be seen by Internet users.

Optical character recognition (OCR) – is the mechanical or electronic conversion of images of typed, handwritten or printed text into machine-encoded text.

Digitizer – It converts analog information into digital form.

Optical Mark reading (OMR) – Optical Mark Readers reads pencil or pen marks made in pre-defined positions on paper forms as responses to questions or tick list prompts.

Basic structure of CPU

CPU (Central processing unit)

A central processing unit (CPU) is the electronic circuitry within a computer that carries out the instructions of a computer program by performing the basic arithmetic, logical, control and input/output (I/O) operations specified by the instructions.

*CPU – Heart of the Computer

*CPU Process:

 1.Fetch the Instruction

2.Interpret the Instruction

3.Fetch the Data

4.Process the Data

5.Write the data

Output devices

An output device is any device used to send data from a computer to another device or user. Most computer data output that is meant for humans is in the form of audio or video. Examples include monitors, projectors, speakers, headphones and printers.

Monitors – A Monitor is a TV-like display attached to the computer on which the output can be displayed and viewed. It can either be a monochrome display or a colour display.

There are two kinds of monitors

1.    CRT (Cathode ray tube) – The cathode ray tube (CRT) is a vacuum tube containing one or more electron guns, and a phosphorescent screen used to view images.

2.    Thin-Film-Transistor Liquid-Crystal Display (TFT LCD) – A thin-film-transistor liquid-crystal display (TFT LCD) is a variant of a liquid-crystal display (LCD) that uses thin-film transistor technology to improve image qualities such as addresability and contrast.

Printer – Printer is a output device for printing text or pictures.

1.    Impact printer – An impact printer is a printer that strikes a print head against an ink ribbon to mark the paper. Common examples include dot matrix and daisy-wheel printers.

2.    Non-Impact printer – Non-impact printers print the characters without using ribbon. Two common types of non-impact printers include inkjet printers, which spray small drops of ink onto each page, and laser printers, which roll ink onto the paper using a cylindrical.

Memory

Primary Memory or Main Memory

Register:

Register is one of a small set of data holding places that are part of the computer processor. A register may hold an instruction, a storage address, or any kind of data (such as a bit sequence or individual characters). Some instructions specify registers as part of the instruction.

1.    RAM (Random access memory) – Random Access Memory (RAM) is a type of data storage used in computers that is generally located on the motherboard. This type of memory is volatile and all information that was stored in RAM is lost when the computer is turned off.

There are two types of Random access memory

• Dynamic RAM – dynamic indicates that the memory must be constantly refreshed (reenergized) or it will lose its contents.
• Static Memory – A computer memory that contains fixed information and retains its programmed state as long as the power is on.

Virtual memory is a feature of an operating system (OS) that allows a computer to compensate for shortages of physical memory by temporarily transferring pages of data from random access memory(RAM) to disk storage.

2. ROM (Read only memory) – Once data has been written onto a ROM chip, it cannot be removed and can only be read. Unlike main memory (RAM), ROM retains its contents even when the computer is turned off.ROM is referred to as being nonvolatile.

There are three types of Read only memory (ROM)

• PROM – PROM stands for Programmable Read Only Memory. This form of ROM is initially blank. The user or manufacturer can write data/program on it by using special devices. However, once the program or data is written in PROM chip, it cannot be changed. If there is an error in writing instructions or data in PROM, the error cannot be erased. PROM chip becomes unusable.
• EPROM – EPROM stands for Erasable Programmable Read Only Memory. This form of ROM is also initially blank. The user or manufacturer can write program or data on it by using special devices. Unlike PROM, the data written in EPROM chip can be erased by using special devices and ultraviolet rays. So program or data written in EPROM chip can be changed and new data can also be added. When EPROM is in use, its contents can only be read.
• EEPROM – EEPROM stands for Electrically Erasable Programmable Read Only Memory. This kind of ROM can be written or changed with the help of electrical devices. So data stored in this type of ROM chip can be easily modified.

3. Cache:

A cache is a place to store something temporarily in a computing environment. Cache memory, also called CPU memory, is random access memory (RAM)

Memory units

Storage capacity is expressed in terms of Bytes. The data is represented as binary digist(0s and 1s)

• Hierachy – Nibble<Bit < Byte < KB < MB < GB < TB < PB < XB < ZB < YB
• American Standard Code for Information Interchange (ASCII) is the standard code the computer industry created to represent characters(more than 64 character)

1	4 bit	Nibble
2	8 bit	1 byte
3	1024 B	1 KB (210)
4	1024 KB	1 MB(220)
5	1024 MB	1 GB(230)
6	1024 GB	1 TB(240)
7	1024 TB	1 PB(250)
8	1024 PB	1 XB(260)
9	1024 XB	1 ZB(270)
10	1024 ZB	1 YB(280)

Secondary memory – Secondary memory is a type of computer memory that is not directly accessed by the central processing unit (CPU) of a computer and is usually available as non-volatile memory. One of the most common forms of this memory is the hard drive of a computer, which is used to store the operating system (OS) and other programs. Other forms of secondary memory include disc drives for compact discs (CDs) or digital versatile discs (DVDs), as well as removable flash memory.

• Hard Drive – a rigid non-removable magnetic disk with a large data storage capacity.
• Floppy disk- A floppy disk, also called a diskette or just disk, is a type of disk storage composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles. Floppy disks are read and written by a floppy disk drive (FDD).
• Magnetic Tape – Magnetic tape used in recording sound, pictures, or computer data.
• Flash memory – a kind of memory that retains data in the absence of a power supply.
• Optical disk – an electronic data storage medium that can be written to and read using a low-powered laser beam.
• CD-ROM: “Read Only” (used for distribution of commercial software, for example) Standard storage capacity is 640MB.
• CD-R (or CD-WORM): “Write Once, Read Many” times
• CD-RW: rewritable multiple times
• DVD: similar to CD, but with significantly larger storage capacity (4.7GB)
• Write once read many (WORM) describes a data storage device in which information, once written, cannot be modified

Mother board – A motherboard is the main circuit board inside a computer that connects the different parts of a computer together. It has sockets for the CPU, RAM and expansion cards (e.g. discrete graphics cards, sound cards, network cards, storage cards etc)… and it also hooks up to hard drives, disc drives and front panel ports with cables and wires.Also known as mainboard, system board.

COMPUTER GENERATIONS AND CLASSIFICATION OF COMPUTER

NETWORKING AND INTERNET

• AGP –>Accelerated Graphic Port
• PC –>Personal Computer
• EPROM –>Erasable Programmable Read Only Memory
• BIOS –>Basic Input and Output System
• HDD –>Hard Disk Drive
• PCI –>Peripheral Component Interconnect
• UNIVAC –>Universal Automatic Computer
• GUI –>Graphic User Interface
• USB –>Universal Serial Bus
• VGA –>Visual Graphic Adaptor
• MAN –>Metropolitan Area Network
• ASCII –>American Standard Code for Information Interchange
• WAN –>Wide Area Network
• EBCDIC –>Extended Binary Coded Decimal Interchange Code
• LAN –>Local Area Network
• EEPROM/EAPROM –>Electrical Erasable/Alterable Programmable Read Only Memory
• CPU –>Central Processing Unit
• OS –>Operating System
• ALU –>Arithmetic and Logic Unit
• DVD –>Digital Versatile Disc
• CD –>  Compact Disk
• ROM –>Read Only Memory
• VDU –>Visual Display Unit
• RAM –>Random Access Memory
• ICT –>Information Communication Technology
• PROM –>Programmable Read Only Memory
• URL –>Universal Resource Locator
• IDE –>Integrated Drive Electronics
• FORTRAN –>Formular Translator
• MOS –>Metaoxide Semi Conductor
• ATX –>Advanced Technology Extended
• SIM –>Subscriber Identification Module
• MHZ –>Megahertz
• ISP –>Internet Service Provider
• GHZ –>Gigahertz
• DBMS –>Database Management System
• SQL –>Structured Query Language
• RW –>Re-Writeable
• SDT –>Serial Data Transmission
• CAN –>Campus Area Network
• SIMMs –>Single In-line Memory Module
• PAN –>Personal Area Network
• DIMMs –>Dual In-line Memory Module
• CMOS –>Complimentary Metaoxide Semi Conductor
• ENIAC –>Electronic Number Integrator And Calculator
• CMD –> Command
• EDSAC –>Electronic Dialog Storage Automatic Computer
• MAC –>Media Acces Control
• IC –>Integrated Circuit
• LSIC –>Large Scale Integrated Circuit
• DIR –>Directory
• GIGO –>Gabbage In Gabbage Out
• PHP –>PHP Hypertext Preprocessor
• DOC –>Document
• PDT –>Parallel Data Transmission
• PDA –>Personal Digital Assistant
• USSD –>Unstructured Supplementary Service Data
• WWW –>World Wide Web
• COBOL

–>Common Basic Oriented Language
• CCNP –>Cisco Certified Network Professionals
• BASIC –>Beginner All Purpose Symbolic Instruction Code
• CEH –>Certified Ethical Hacking
• TCP –>Transmission Control Protocol
• CSS –> Cascading Style Sheet
• CISCO –>Computer Information System Company
• XXS –>Cross Site Scripting
• XML –>Extensible Mark-up Language
• HTML –>Hypertext Markup Language
• CCNA –>Cisco Certified Network Associate
• RFI –>Remote File Inclusion
• HTTP –>Hypertext Transfer Protocol
• DDOS –>Distribution Denial Of Service
• VPN –>Virtual Private Network
• SEO –>Search Engine Optimization
• IP Internet Protocol

Operating Systems and Data Storage Based

• BIOS – This is the Basic Input Output System which controls the computer, telling it what operations to perform. These instructions are on a chip that connects to the motherboard.
• BYTE – A byte is a storage unit for data.

·          

• “K” is a Kilobyte which is 1024 bytes.
• “MB” is a Megabyte which is a million bytes.
• “GB” is a Gigabyte, which equals 1000 megabytes.
• CPU – This stands for the Central Processing Unit of the computer. This is like the computer’s brain.
• MAC – This is an abbreviation for Macintosh, which is a type of personal computer made by the Apple Computer company.
• OS – This is the Operating System of the computer. It is the main program that runs on a computer and begins automatically when the computer is turned on.
• PC – This is the abbreviation for personal computer. It refers to computers that are IBM compatible.
• PDF– This represents the Portable Document Format which displays files in a format that is ready for the web.
• RAM – This stands for Random Access Memory which is the space inside the computer that can be accessed at one time.  If you increase the Amount of RAM, then you will increase the computer’s speed. This is because more of a particular program is able to be loaded at one time.
• ROM – This is Read Only Memory which is the instruction for the computer and can not be altered.
• VGA – The Video Graphics Array is a system for displaying graphics. It was developed by IBM.
• WYSIWYG – This initialism stands for What You See Is What You Get.  It is pronounced “wizziwig” and basically means that the printer will print what you see on your monitor.

Connecting to the Internet Network Based

• FTP – This is a service called File Transport Protocol which moves a file between computers using the Internet.
• HTML – HyperText Markup Language formats information so it can be transported on the Internet.
• HTTP – Hypertext Transfer Protocol is a set of instructions for the software that controls the movement of files on the Internet.
• IP – This stands for Internet Protocol which is the set of rules that govern the systems connected to the Internet. IP Address is a digital code specific to each computer that is hooked up to the Internet.
• ISP – The Internet Service Provider is the company which provides Internet service so you can connect your computer to the Internet.
• LAN – This stands for Local Area Network which is the servers that yourcomputer connects to in your geographic area.
• PPP – Point-to-Point Protocol is the set of rules that allow your computer to use the Internet protocols using a phone line and modem.
• URL – This is the Uniform Resource Locator which is a path to a certain file on the World Wide Web.
• USB – The Universal Serial Bus is used for communications between certain devices. It can connect keyboards, cameras, printers, mice, flash drives, and other devices. Its use has expanded from personal computers to PDAs, smartphones, and video games, and is used as a power cord to connect devices to a wall outlet to charge them.
• VR – Virtual Reality simulates a three-dimensional scene on the computer and has the capability of interaction. This is widely used in gaming.
• VRML – Virtual Reality Mark-up Language allows the display of #D Images.

Some Common Email Abbreviations

Here is a list of email abbreviations that are commonly used to get your point across in less time and fewer keystrokes:

• 2G4U – Too Good For You
• AWHFY – Are We Having Fun Yet?
• AYPI – And Your Point Is?
• GAL – Get A Life
• GMTA – Great Minds Think Alike
• J4F – Just For Fun
• KISS – Keep it Simple, Stupid
• QL – Quit Laughing!
• RUOK – Are you Okay?
• SITD – Still In The Dark
• TIC – Tongue In Cheek
• WYSIWYG – What You See Is What You Get
• YYSSW – Yeah Yeah Sure Sure Whatever
• ZZZ – Sleeping, Bored, Tired

Here are some Computer full forms, If you know more Full forms please share here so that we all know about them as well :)
1. *PAN* - permanent account number.
2. *PDF* - portable document format.
3. *SIM* - Subscriber Identity Module.
4. *ATM* - Automated Teller machine.
5. *IFSC* - Indian Financial System Code.
6. *FSSAI(Fssai)* - Food Safety & Standards Authority of India.
7. *Wi-Fi* - Wireless fidelity.

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8. *GOOGLE* - Global Organization Of Oriented Group Language Of Earth.
9. *YAHOO* - Yet Another Hierarchical Officious Oracle.
10. *WINDOW* - Wide Interactive Network Development for Office work Solution.
11. *COMPUTER* - Common Oriented Machine. Particularly United and used under Technical and Educational Research.
12. *VIRUS* - Vital Information Resources Under Siege.
13. *UMTS* - Universal Mobile Telecommunicati ons System.
 14. *AMOLED* - Active-matrix organic light-emitting diode.
15. *OLED* - Organic light-emitting diode.
16. *IMEI* - International Mobile Equipment Identity.
17. *ESN* - Electronic Serial Number.
18. *UPS* - Uninterruptible power supply.
19. *HDMI* - High-Definition Multimedia Interface.
20. *VPN* - Virtual private network.
21. *APN* - Access Point Name.
22. *LED* - Light emitting diode.
23. *DLNA* - Digital Living Network Alliance.
24. *RAM* - Random access memory.
25. *ROM* - Read only memory.
26. *VGA* - Video Graphics Array.
27. *QVGA* - Quarter Video Graphics Array.
28. *WVGA* - Wide video graphics array.
29. *WXGA* - Widescreen Extended Graphics Array.
30. *USB* - Universal serial Bus.
31. *WLAN* - Wireless Local Area Network.
32. *PPI* - Pixels Per Inch.
33. *LCD* - Liquid Crystal Display.
34. *HSDPA* - High speed down-link packet access.
35. *HSUPA* - High-Speed Uplink Packet Access.
36. *HSPA* - High Speed Packet Access.
37. *GPRS* - General Packet Radio Service.
38. *EDGE* - Enhanced Data Rates for Global Evolution.
39. *NFC* - Near field communication.
40. *OTG* - On-the-go.
41. *S-LCD* - Super Liquid Crystal Display.
42. *O.S* - Operating system.
43. *SNS* - Social network service.
44. *H.S* - HOTSPOT.
45. *P.O.I* - Point of interest.
46. *GPS* - Global Positioning System.
47. *DVD* - Digital Video Disk.
48. *DTP* - Desk top publishing.
49. *DNSE* - Digital natural sound engine.
50. *OVI* - Ohio Video Intranet.
51. *CDMA* - Code Division Multiple Access.
52. *WCDMA* - Wide-band Code Division Multiple Access.
53. *GSM* - Global System for Mobile Communications.
54. *DIVX* - Digital internet video access.
55. *APK* - Authenticated public key.
56. *J2ME* - Java 2 micro edition.
57. *SIS* - Installation source.
58. *DELL* - Digital electronic link library.
59. *ACER* - Acquisition Collaboration Experimentation Reflection.
60. *RSS* - Really simple syndication.
61. *TFT* - Thin film transistor.
62. *AMR*- Adaptive Multi-Rate.
63. *MPEG* - moving pictures experts group.
64. *IVRS* - Interactive Voice Response System.
65. *HP* - Hewlett Packard.

Concepts of data representation in digital computers

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• Data and instructions cannot be entered and processed directly into computers using human language. Any type of data be it numbers, letters, special symbols, sound or pictures must first be converted into machine-readable form i.e. binary form. Due to this reason, it is important to understand how a computer together with its peripheral devices handles data in its electronic circuits, on magnetic media and in optical devices.

Data representation in digital circuits

• Electronic components, such as microprocessor, are made up of millions of electronic circuits. The availability of high voltage(on) in these circuits is interpreted as ‘1’ while a low voltage (off) is interpreted as ‘0’.This concept can be compared to switching on and off an electric circuit. When the switch is closed the high voltage in the circuit causes the bulb to light (‘1’ state).on the other hand when the switch is open, the bulb goes off (‘0’ state). This forms a basis for describing data representation in digital computers using the binary number system.

Data representation on magnetic media

• The laser beam reflected from the land is interpreted, as 1.The laser entering the pot is not reflected. This is interpreted as 0.The reflected pattern of light from the rotating disk falls on a receiving photoelectric detector that transforms the patterns into digital form. The presence of a magnetic field in one direction on magnetic media is interpreted as 1; while the field in the opposite direction is interpreted as “0”.Magnetic technology is mostly used on storage devices that are coated with special magnetic materials such as iron oxide. Data is written on the media by arranging the magnetic dipoles of some iron oxide particles to face in the same direction and some others in the opposite direction

Data representation on optical media 

In optical devices, the presence of light is interpreted as ‘1’ while its absence is interpreted as ‘0’.Optical devices use this technology to read or store data. Take example of a CD-ROM, if the shiny surface is placed under a powerful microscope, the surface is observed to have very tiny holes called pits. The areas that do not have pits are called land.

Reason for use of binary system in computers

• It has proved difficult to develop devices that can understand natural language directly due to the complexity of natural languages. However, it is easier to construct electric circuits based on the binary or ON and OFF logic. All forms of data can be represented in binary system format. Other reasons for the use of binary are that digital devices are more reliable, small and use less energy as compared to analog devices.

Bits, bytes, nibble and word

• The terms bits, bytes, nibble and word are used widely in reference to computer memory and data size.
• Bits: can be defined as either a binary, which can be 0, or 1.It is the basic unit of data or information in digital computers.

• Byte: a group of bits (8 bits) used to represent a character. A byte is considered as the basic unit of measuring memory size in computer.
• A nibble: is half a byte, which is usually a grouping of 4 bits.

• Word: two or more bits make a word. The term word length is used as the measure of the number of bits in each word. For example, a word can have a length of 16 bits, 32 bits, 64 bits etc.