1. INTRODUCTION TO COMPUTERS
LESSON 1
INTRODUCTION TO COMPUTERS
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2. LESSON OVERVIEW DEFINITION OF COMPUTER UNITS OF MEASUREMENT
CLASSIFICATION OF COMPUTERS
PARTS OF AN INFORMATION SYSTEM
DEVELOPMENTS IN COMPUTERS
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3. 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.
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4. UNITS OF MEASUREMENT IN COMPUTING
Storage
Speed
Time
Frequency
Unit
Symbol
Byte
bit per second
second
Hertz B
Bps s Hz
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5. 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)
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6. 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
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7. CLASSIFICATION OF COMPUTERS BY PURPOSES
A general-purpose computer
A special purpose computer
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8. CLASSIFICATION OF COMPUTERS ACCORDING TO MEMORY SIZE AND COST
Microcomputers
Minicomputers
Mainframe computers
Supercomputers
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9. CLASSIFICATION OF COMPUTERS
Computers can also be classified based On General Performance Levels.
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10. CLASSIFICATION OF COMPUTERS ACCORDING TO THE TYPE OF DATA PROCESSED
Analogue
Digital
Hybrid
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11. 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.
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12. PARTS OF AN INFORMATION SYSTEM
People
Procedures
Software
Hardware
Data
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13. 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
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14. SOME APPLICATIONS IN BUSINESS AND MANUFACTURING
TradeNet
Computer Aided Design
Registry of Companies Enquiry System
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15. 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
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16. 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.
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17. 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.
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18. 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
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19. 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
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20. 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.
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21. 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).
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22. 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. .
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23. 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.
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24. 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.
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25. 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
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26. 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
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