Computer

Computer:

               Computer is an electronic device that works with numbers & symbols, takes an input, process it and gives an output.

                 The word computer is derived from the Latin word "Computare" which means to calculate.

 Data:

                Data is a collection of unorganized or raw facts which may include letters of alphabets, digits,graphics and sounds.

Instruction:

                 Instruction are the commands or order given to the computer to perform specific tasks. 

Program:

                 A set of instructions written in any computer language, that performs a specific task is called a program.

Basic (working) principle of a computer :

1.  Input
2. Processing
3. Output

Input :

              The data and instruction fed to the computer are known as Input. We use input devices like keyboard, mouse etc to input data and instruction to the computer. 

Processing :

               The treatment of data as per given instructions to convert them into meaningful information is called processing. CPU ( microprocessor ) of the computer does the processing task.

 

Output :

              The result of processing or other information is output . We see the result of processing on the output devices like monitor, printer, etc.

 

Characteristics (Features) of computer :

                 The main characteristics of computer are as follows :

1. Speed
2. Accuracy
3. Diligence
4. Versatile
5. Storage
6. Automatic

Speed :

                 One of the capabilities of the computer is its processing speed. Computer works or operates on electrical signals, usually called electric pulses. Since electric pulses travel at very fast speed, so computer works at very high speed. The speed of computer is measured in second.

Accuracy:

                 Computer give accurate results. Computers are 100% accurate. They never give wrong information. It's the human beings who does the mistake in instructing the computer. If the input (data or information) is wrong, then the result of processing will not be what we expect. This type of error in computer is known as Garbage In Garbage Out (GIGO).

Diligence :

                 A computer can perform tasks repeatedly for a long time with the same speed and accuracy. Such capability of computer is known as diligence. It never gets tired doing same job again and again.

Versatile :

                 A computer can be used for performing various types of tasks. It can be used for making documents, spreadsheets, presentations, composing songs, etc so it is also known as versatile machine.

Storage :

                   Computers can store large amount of information, data or programs in the secondary storage device like Hard Disk, Compact Disk(CD), Digital Versatile Disk(DVD),  etc. The storage capacity of such device is measured in bytes. One byte is the amount of storage needed to store one character. 

1 Bit = 0 or 1

4 Bits = 1 Nibble

8 Bits or 2 Nibbles = 1 Byte

1024 Bytes = 1 KB(Kilo Byte)

1024 KB = 1 MB (Mega Byte)

1024 MB = 1 GB (Giga Byte)

Automatic :

                  Once we have fed instruction to the computer we don't need to instruct it again and again. It performs tasks automatically once the instruction is given.