Gaussian Integer

A Gaussian integer is a complex number a + b i, where a and b are integers and i is the imaginary unit.

Gaussian integer is a college-level concept that would be first encountered in an abstract algebra course covering rings and fields.

i:	i is the symbol used to denote the principal square root of -1, also called the imaginary unit.

Algebraic Number:	An algebraic number is a number that is the root of some polynomial with integer coefficients. Algebraic numbers can be real or complex and need not be rational.
Complex Number:	A complex number is a number consisting of a real part and an imaginary part. A complex number is an element of the complex plane.
Field:	A field is a ring in which every nonzero element has a multiplicative inverse. The real numbers and the complex numbers are both fields.
Integer:	An integer is one of the numbers ..., -2, -1, 0, 1, 2, ....