General Concepts of Computer

• A computer is a device that automatically performs Arithmetic or Logical operations on information input to it and provides an output according to the performed set of instructions stored within it.
• Hardware,Software and Firmware together make up a computer system.
• Computers understand only binary number system, which has only two digits i.e. zero(0) and one(1) .
• A single Binary digit is called Bit. The Smallest Unit of Representing data in a computer.
• A set of binary patterns include the letters(A-Z), decimal digits(0-9) and certain special characters such as punctuations mark are known as alpha numeric character set.
• A group of 4 bits is called one nible .
• A group of 8 bits is called as one byte.
• A group of 1024 bytes is called as one kilo byte (KB).
• A group of 1024 KB is called as one Megabyte (MB).
• A group of 1024 MB is called as one Gigabyte (GB).
• A group of 1024 GB is called as one Terabyte (TB).

b=bits

B=bytes

0 or 1= 1 bit

eg:- CM =

C=0010

M=0012

A computer’s word is a group of bits the length of which varies from machine to machine. The word may be as long as 64bits or as short as 4bits.

Word length determines the number of bits CPU moves internally i.e between your processor and memory and externally between your memory and device.