A negative number is a real number that is less than zero in mathematics. Negative numbers are the polar opposites of positive numbers. Positive denotes a rightward movement, while negative denotes a leftward movement. Negative represents below sea level, while positive represents above sea level. A deposit is represented by a positive number, while a withdrawal is represented by a negative number. They’re commonly used to express the size of a loss or deficiency. A owed debt can be considered a negative asset, and a reduction in a quantity can be considered a negative increase.