Addition!
addition is when you add two or more things together.
and to add two things together, you need "+"!
but to get the result you need "=".
that symbol is the plus symbol, which is one of many operators.
an operator is a symbol that does something to numbers.
for example:
1 + 1 = 2.
because, the order of numbers, makes 1 + 1 = 2.
so 2 + 2 = 4.