In order to know about irrational numbers, first let us learn about rational numbers. Rational numbers are the numbers that can be written in fractional form where both the numerator and denominator are integers and the denominator is not equal to zero. Irrational numbers can also be said as a number which can be represented in the fractional form as $\frac{P}{Q}$ where Q is not equal to 0 and P, Q are both Integers.

A number is said to be an irrational number, if we are not able to express it as an integer's quotient. $\frac{p}{q}$, q $\neq$ 0. Examples of irrational numbers are $\sqrt{5}$, $\sqrt{13}$, $\sqrt{11}$, etc... The irrational numbers definition is as follows:

Real number which are not Rational numbers are called as Irrational Numbers.