If you have created your own variables and assigned them each a value (such as a string or integer), then you will already be familiar with the assignment operator which is a single = (equals sign).

There are other operators used for calculations though such as adding, subtracting, multiplying, dividing, increasing and decreasing values, etc. Take a look at the source code to see what is available.

Make sure you also watch the video about operators here.

<!DOCTYPE html>
<html lang="en"
 <meta charset="utf-8"/>
 <title>JavaScript - Operators</title>
 <script type="text/javascript">
 var x = 5, y = 10; //variables can be initialised on one line, separated by commas
 var z = x + y; // this is how variables can be added
 z++ //this increases the z variable value by 1
 z-- //this decreases the z variable value by 1
 // operators include + (plus) - (minus) * (multiply) / (divide) and % (modulus) which returns the remainder from division
 x+=y; //this is an example of compound addition. It is the equivalent of x = x + y
 // variables can be added using the compound addition += , compound subtraction -= , compound multiplication *= or compound addition /=
 document.write(z); // now let's see what the z variable displays after these modifications.