According to MathGoodies.com, zero is a neutral number or integer since it is neither negative nor positive. Whole numbers to the right of zero, or greater than zero, are known as positive integers. Whole numbers to the left of zero, or less than zero, are known as negative integers.
Two integers on a number line the same distance from zero are known as opposites, an example being -3 and +3. The term integers is defined as the "set of whole numbers and their opposites." According to Reference.com, non-negative integers or positive integers greater than zero, are also known as "natural numbers." Zero is also a natural number.