What is the difference between rational and irrational numbers?

A rational number is a number that can be written as a fraction, or a ration, an irrationalnumber can be written as a decimal but not a fraction

A rational number can be written as a ratio (fraction) and an irrational number cannot.

For example, 5 is a rational number because it can be written as 5/1, but π cannot be written as a fraction, because it is a never ending, never repeating decimal. (3.141592653589793 ...)