Data Representation in computer

DATA REPRESENTATION

NUMBER SYSTEM

A mathematician Marquis de laplace gave birth to the number system. A number system of radix (also known as base) r is a system. These system have r different symbol for r digits. The digits represent values, depend on the position they occupy in a number. A group of symbolic digits represents a number. For a computer everything is a number like numerical values (numbers), letters, sound, pictures, instructions etc. When, we look letter of the alphabet on a desktop. We see just one of the computer's ways of representing numbers.

For instance, see the following sentence:

A    01000001
r     01110010
v    01110110
i     01101001
n    01101110
d    01100100
      00100000
i     01101001
s     01110011
      00100000
a    01100001
n    01101110
      00100000
u    01110101
t     01110100
h    01101000
o    01101111
.     00101110 

The sentence may look like a group (string) of alphabetic character to us. But it looks like a string of zero and ones as shown in the above figure.

When we want to represent the quantity of that number, we multiply each digit by an integer power of r and then form the sum of all weighted digtits.

For instance, a string of number 2468 can be represented in quantity as 2x10**3+4x10**2+6x10**1+8x10*0

There are four types of numbers system as follows:

• Decimal number system
• Binary number system
• Octal number system
• Hexadecimal number system