The plus sign (+) means "ADD" in programming and on calculator keyboards. For example, 10 + 7 means 10 added to 7. It is also used as a concatenation symbol for text fields. For example ...

For addition we normally use the plus sign ("+") and for subtraction we use the minus sign ("+") and subtraction ... came from the Latin word 'et' meaning ‘and’.

Statistically, the most common symbol in mathematics is the equal sign, which appears in 94% of mathematical expressions.