Rational numbers are general terms for integers and fractions, and all rational numbers can be converted into component numbers.

Irrational number, that is, the real number of irrational number, cannot be written as the ratio of two integers. If written in decimal form, there are infinitely many digits after the decimal point, which will not cycle. Common irrational numbers include most square roots, π and E (the latter two are transcendental numbers at the same time).