Though the signs now seem as familiar as the alphabet or the Hindu–Arabic numerals, they are not of great antiquity. The Egyptian hieroglyphic sign for addition, for example, resembled a pair of legs walking in the direction in … See more

The plus sign (+) is a binary operator that indicates addition, as in 2 + 3 = 5. It can also serve as a unary operator that leaves its operand unchanged (+x means the same as x). This notation may be used when it is desired to … See more

The minus sign (−) has three main uses in mathematics:
1. The subtraction operator: a binary operator to indicate the operation of subtraction, as in 5 − 3 = 2. Subtraction is the inverse of addition. … See more

Some elementary teachers use raised minus signs before numbers to disambiguate them from the operation of subtraction. The same convention is also used in some computer languages. For example, s… See more

When placed after a number, a plus sign can indicate an open range of numbers. For example, "18+" is commonly used as shorthand for "ages 18 and up".
In grading systems (such as examination marks), th… See more

As well as the normal mathematical usage, plus and minus signs may be used for a number of other purposes in computing.
Plus and minus signs are often used in tree view on a computer screen—to show if a folder is col… See more