The set of rational numbers, denoted by the symbol , is defined as any number that can be represented in the form of where and belong to the set of integers and is non-zero. The set of rational numbers gives good coverage over the number line but notably does not contain irrational, complex, or transcendental numbers.

The set of integers, denoted as ℤ, includes all positive and negative whole numbers, along with zero. For example, the numbers -2, 0 and 3 are all integers, but numbers like 1/2 or the square root of 2 are not.

The set of real numbers includes all rational and irrational numbers. It represents the entire continuum of possible number values from negative infinity to positive infinity.

The set of complex numbers contains all possible complex numbers. Each complex number has a real part and an complex part.