For the need of statistics, negative numbers are introduced. For example, in these cases, borrowing, profit and loss, and in and out all use negative numbers to represent opposite quantities.

Negative number is a mathematical term. Numbers less than 0 are called negative numbers, and negative numbers and positive numbers represent quantities with opposite meanings. Negative numbers are marked with a minus sign (minus sign).

Symbol, equivalent to minus sign) "-"and a plus sign, such as? 2 stands for the antonym of 2. Therefore, any positive number preceded by a negative sign becomes a negative number.