2. Introduction of Computer  A computer is an electronic device which calculates the raw data and gives valuable information which is the result of processing.  A computer is a programmable electronic machine that can perform a variety of tasks at very high speed and accuracy.  It is also called processing and manipulating device.

3. Appearance of Computer

4. Features/Characteristics of Computer Characteristics of computer Accuracy : Computers are perfectly accurate i.e. they are 100% accurate. Storage: computer can store huge number of data. Diligence: A computer can work for long time without losing its accuracy and speed. Speed : The speed of computer is measured in fraction of a second which we call nano second or pico second. Reliability : computers are reliable since they have great speed and they are very accurate.

5. Speed A computer can execute instruction or command at a very fast speed. Speed of a computer is affected by: clock cycle, cache memory, size of storage device, capacity of microprocessor etc. The time taken to perform any task by a computer is called speed of the computer. Millisecond One thousandth of a second (10 -3 ) (1/1000) Microsecond One millionth of a second of a second (10 -6 ) Nanosecond one billionth of a second (10 -9 ) Picosecond one trillionth of a second (10 -12 )

6. Storage 1 bit0 or 1 1 Byte8 bits Nibble4 bits 1 KB1024 Byte 1MB1024 KB 1GB1024 MB 1 TB2024 GB 1PB2024 TB

7. Word Length It is a processing capacity of a computer. The word length of a computer is in power of 2 for e.g. * bits, 16 bits, 64 bits and so on. A computer with word length of 64bits is also known as 64 bit computer. The grater the word length of a computer the higher the speed will be.

8. Application areas of computers

9. Education Sector

10. Medical sector

11. Financial sector

12. Offices

13. Entertainment sector

14. Computer Peripherals The equipment connected with computer for its use are called computer. The computer peripherals in connection vary as required.

15. ADVANTAGES OF COMPUTER It stores large amount of data It process data with high speed It can perform repetitive tasks it is an automatic machine It is a versatile machine

16. Disadvantages of Computer  It requires a normal temperature to operate  All people cannot afford the computer  It requires regular repair  It requires skilled manpower to work with the computer

17. Limitations of Computer  It requires regular power supply to operate  It is a non-intelligent machine. It cannot think and give the decisions  Computer cannot memorize and recall  It needed instructions to perform a task.

18. Full forms: IBM – International Business Machine GIGO – Garbage in Garbage out ATM – Automated Teller machine ICU - Intensive Care Unit RAM – Random Access Memory ROM – Read only memory KB - Kilo byte MB - Mega Byte GB - Giga Byte TB - Tera Byte PB – Peta Byte

19. Thank You Dipendra Bhusal E-mail: dipendrabhusal133@gmail.com