INTRODUCTION TO COMPUTERS LESSON 1 INTRODUCTION TO COMPUTERS Copyright @ Genetic Computer School 2008

LESSON OVERVIEW DEFINITION OF COMPUTER UNITS OF MEASUREMENT CLASSIFICATION OF COMPUTERS PARTS OF AN INFORMATION SYSTEM DEVELOPMENTS IN COMPUTERS Copyright @ Genetic Computer School 2008

DEFINITION OF COMPUTER A computer may be defined as an electronic machine, which accepts data from an input device, processes it by performing arithmetical and logical operations in accordance with a program of instructions and returns the results through an output unit. Copyright @ Genetic Computer School 2008

UNITS OF MEASUREMENT IN COMPUTING Storage Speed Time Frequency Unit Symbol Byte bit per second second Hertz B Bps s Hz Copyright @ Genetic Computer School 2008

THE FUNDAMENTAL UNIT OF STORAGE The fundamental unit of storage is the byte (also called character). When counting bytes we deal in powers of 2 such as 210 called a kilobyte (Kb) 220 called a megabyte (Mb) 230 called a gigabyte (Gb) 240 called terabyte (Tb) Copyright @ Genetic Computer School 2008

CLASSIFICATION OF COMPUTERS Classification Of Computers By Purposes Classification Of Computers According To Memory Size And Cost Classification Of Computers Based On General Performance Levels Classified Of Computers According To The Type Of Data Processed Classification Of Computers According To Generations Copyright @ Genetic Computer School 2008

CLASSIFICATION OF COMPUTERS BY PURPOSES A general-purpose computer A special purpose computer Copyright @ Genetic Computer School 2008

CLASSIFICATION OF COMPUTERS ACCORDING TO MEMORY SIZE AND COST Microcomputers Minicomputers Mainframe computers Supercomputers Copyright @ Genetic Computer School 2008

CLASSIFICATION OF COMPUTERS Computers can also be classified based On General Performance Levels. Copyright @ Genetic Computer School 2008

CLASSIFICATION OF COMPUTERS ACCORDING TO THE TYPE OF DATA PROCESSED Analogue Digital Hybrid Copyright @ Genetic Computer School 2008

CLASSIFICATION OF COMPUTERS ACCORDING TO GENERATIONS First  By the use of vacuum tubes Second By the use of transistors in their manufacture Third By having greater reduction in size due to the use of integrated circuits Fourth By having the entire processor on a chip through the use of very large scale integration (VLSI) in their manufacture Fifth By the use of artificial intelligence, large capacity erasable optical discs, transputer based processing systems, and perhaps voice recognition as well. Copyright @ Genetic Computer School 2008

PARTS OF AN INFORMATION SYSTEM People Procedures Software Hardware Data Copyright @ Genetic Computer School 2008

DEVELOPMENTS OF COMPUTERS Connectivity / Internet Connectivity Networking of computers Convergence of computing and communications Applications of IT Smaller but faster Computer Cheaper in Price Larger storage capacity Copyright @ Genetic Computer School 2008

SOME APPLICATIONS IN BUSINESS AND MANUFACTURING TradeNet Computer Aided Design Registry of Companies Enquiry System Copyright @ Genetic Computer School 2008

MAGNETIC STRIPE TECHNOLOGY is one of the most universal methods in Automatic Identification and Data Capture (AIDC) industry. is used everywhere, credit cards, ID cards, ATM cards, security control of selected rooms or buildings, time and attendance cards, factory floor data collection cards, driver's licenses, mass transits tickets, airline tickets and many more. is known as a handy and cost-effective way of carrying a practical amount of rewritable and machine-readable data using magnetic storage technology. uses magnetic material to store data. is printed on paper or plastic stores data instead of sound and images Is designed to be directly handled is often used for reading by manually swiping Copyright @ Genetic Computer School 2008

ESSENTIAL FACTORS AFFECTING THE MAGNETIC RECORDING AND REPLAY PROCESS The two most essential factors affecting the magnetic recording and replay process are head to medium partition and traveling speed of the medium. Copyright @ Genetic Computer School 2008

COERCIVITY Coercivity is defined as the strength of the flux reversals in the magnet, or in other words the resistance of the material to demagnetization. Copyright @ Genetic Computer School 2008

ADVANTAGES OF USING MAGNETIC STRIPE TECHNOLOGIES Data can be modified or rewritten High data capacity in relation to bar codes Add security since it is not in human readable form Immune to contamination with dirt, water, oil, moisture, etc No moving components, physically robust Well established standards No consumables required for writing or rewriting Copyright @ Genetic Computer School 2008

DISADVANTAGES OF USING MAGNETIC STRIPE TECHNOLOGY It doesn't work in a distance, thus requiring close contact to the reader Data can be damaged by stray magnetic fields Since it's not in human readable form can be a disadvantage in some applications Copyright @ Genetic Computer School 2008

STANDARDS OF MAGNETIC STRIPE Physical standards Physical standards identify the locations of recording track, encoding methods, data densities and magnetic recording qualities. Application standards Application standards deal with content of data and data format for different applications. Copyright @ Genetic Computer School 2008

SMART CARD (TECHNOLOGY) The inside of a smart card usually contains an embedded microprocessor. The microprocessor is under a gold contact pad on one side of the card for security. The host computer and card reader actually "talk" to the microprocessor. The microprocessor enforces access to the data on the card. If the host computer read and wrote the smart card's random access memory (RAM). 1 of 4 Copyright @ Genetic Computer School 2008

SMART CARD (TECHNOLOGY) Smart cards typically hold 2,000 to 8,000 electronic bytes of data (the equivalent of several pages of data). Because those bytes can be electronically coded, the effective storage capacity of each card is significantly increased. Smarts cards may have up to 8 kilobytes of RAM, 346 kilobytes of ROM, 256 kilobytes of programmable ROM, and a 16-bit microprocessor. . 2 of 4 Copyright @ Genetic Computer School 2008

SMART CARD (TECHNOLOGY) The smart card uses a serial interface and receives its power from external sources like a card reader. The processor uses a limited instruction set for applications such as cryptography. Smart cards can be a carrier of multiple records for multiple purposes. Smart cards are secure, compact and intelligent data carriers. 3 of 4 Copyright @ Genetic Computer School 2008

SMART CARD (TECHNOLOGY) Smart cards can be used with a smart-card reader attachment to a personal computer to authenticate a user. Web browsers also can use smart card technology to supplement Secure Sockets Layer (SSL) for improved security of Internet transactions. Smart-card readers can also be found in mobile phones and vending machines. 4 of 4 Copyright @ Genetic Computer School 2008

THE MOST COMMON SMART CARD APPLICATION Banking Satellite TV Credit cards Electronic cash Computer security systems Wireless communication Loyalty systems (like frequent flyer points) Government identification Copyright @ Genetic Computer School 2008

Image Technology It is used in Computerize the identity cards Finger print scanner Security -video camera/recorder Bar code scanner Laser engravers Application of multimedia in learning Copyright @ Genetic Computer School 2008