**number**is a mathematical object.Number is used to count, measure. The examples are the natural numbers 1, 2, 3, and so on. A notational symbol that represents a number is called a numeral. In common usage, the term number may refer to a symbol, a word, or a mathematical abstraction.an arithmetical value, expressed by a word, symbol, or figure, representing a particular quantity and used in counting and making calculations.

### Types of Number’s

- Natural Number
- Absolute Rational Number
- Relative Rational Number
- Real Number
- Integers

### Natural Numbers

The Counting number’s 1,2,3,4,5,6………….. are known as natural number’s.The set of natural number is denoted by N.

**N={1,2,3,4 ……….}**

**Set :** A set is a collection os well defined objects.The objects that constitute a set are known as its ‘elements ‘ or ‘members’.

### Absolute Rational Numbers

absolute rational number’s are those number’s which can be represented as [pmath size=18]p/q [/pmath]** ** in which p

and **q** [pmath size=18] {in} [/pmath] **N** and [pmath size=18] q <> 0[/pmath].

### Relative Rational Numbers

Relative rational number’s are absolute rational number preceded by [pmath size=18]+[/pmath]** or** [pmath size=18]-[/pmath] sign.

### Absolute Irrational Numbers

Absolute irrational number are those numbers which cannot be represented as [pmath size=18]p/q [/pmath]** **or we can say that such number can not be expressed as fractions e.g [pmath size=18] sqrt{2},log 7 , {pi}[/pmath]