About
An operator is a symbol (token) that compose an expression.
It operates on values on its side (left and/or right).
They represents a function but where the argument are on both side of it.
<MATH> ie \\ \text{ }\\ c = a + b \\ \text{ }\\ \text{is equivalent to} \\ \text{ }\\ c = f(a,b) </MATH>
This function are mathematical function (ie they return the same data type than their input)
Operators can also be seen as actions on variables and values.
Articles Related
Management
Type
Order
Grammar - (Order of (operations|precedence)|operator precedence)
Example
Simple Form
a + b
Assignment
var += a
// equivalent of
var = var + a
See Assignment