Operators

Operators take one or two values (or variables), perform an operation, and return a value. Let's check out a simple example of using an operator, just to clarify the terminology:

> 1 + 2;
3

In this code:

  • + is the operator
  • The operation is addition
  • The input values are 1 and 2 (the input values are also called operands)
  • The result value is 3
  • The whole thing is called an expression

Instead of using the values 1 and 2 directly in the expression, you can use variables. You can also use a variable to store the result of the operation, as the following example demonstrates:

> var a = 1;
> var b = 2;
> a + 1;
2
> b + 2;
4
> a + b;
3
> var c = a + b;
> c;
3

The following table lists the basic arithmetic operators:

Operator symbol

Operation

Example ...

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