The Numbers are the basic units of processing to be done in mathematics. Numbers are taken as input in different procedures of mathematical operations and their output produced on the other side is also a number. Numbers are used for counting and measurement purposes in different areas.

Notational symbol representing a number is called a numeral and numbers are classified into many Sets called number system. Some of the common types of numbers are Natural Numbers, whole numbers, integer, rational numbers, real numbers, complex numbers, even numbers, odd Numbers, prime numbers and composite numbers. These number types are discussed below:

Notational symbol representing a number is called a numeral and numbers are classified into many Sets called number system. Some of the common types of numbers are Natural Numbers, whole numbers, integer, rational numbers, real numbers, complex numbers, even numbers, odd Numbers, prime numbers and composite numbers. These number types are discussed below:

**Natural numbers:**Natural numbers are very familiar like one, two, and three and so on. And generally the sequence of natural number is started with 1.**Whole numbers:**Whole numbers are natural numbers including 0.**Integer:**Integers are the numbers formed by Natural Numbers including 0 along with the negatives of the non-zero natural numbers.**Rational numbers:**Rational numbers are the numbers which can be expressed in the form of fraction, $\frac{p}{q}$, where ‘p’ and ‘q’ are integers and ‘q’ is not equals to 0.**Real numbers:**Real numbers include all the measuring numbers in the number system.**Complex number:**Complex numbers include all the numbers in the form p+ iq, where ‘p’ and ‘q’ are Real Numbers and 'p' is the real part and ‘q’ is the imaginary part.**Even Numbers:**The numbers which are divisible by 2 are called Even Numbers. 2, 4, 6,.. is the series of even numbers. We also say that the numbers which can form pairs are even numbers.**Odd Numbers:**The numbers which are not divisible by 2 are called Odd Numbers. 1, 3, 5,.. is the series of odd numbers, the numbers which cannot form pairs are called odd numbers.**Prime Numbers:**Prime Numbers. The numbers which are the factors of 1 and itself are all called prime numbers. 2, 3, 5, 7, 11... Are the numbers which are divisible by 1 and itself. 2 is the even prime number.**Composite numbers:**The numbers which have the factors more than 2, i.e. the numbers having the factors than 1 and itself are called composite numbers. 4, 6, 8, 9… Are some of the composite numbers. We observe that all the even numbers except 2 are called composite numbers.