There are following types of operators in JavaScript.

1- Arithmetic Operators ( +,-,*,/,%,++,-- )

<script>
var a= 1;
var b = 2;
var c = a + b;
document.getElementById("demo").innerHTML = c;
</script>

2- Comparison (Relational) Operators (==,===,!=,!==,>,>=,<=)

<script type="text/javascript">
                     var a = 5;
            var b = 8;
            var linebreak = "<br />";
            document.write("(a == b) => ");
            result = (a == b);
            document.write(result);
            document.write(linebreak);
            document.write("(a < b) => ");
            result = (a < b);
            document.write(result);
            document.write(linebreak);
</script>

3-Bitwise Operators ( &,|,<<,>>,>>>, =>)

<script type="text/javascript">
         <!--
            var a = 2; //variable taken
            var b = 3;
            var linebreak = "<br />";
            document.write("(a & b) => ");
            result = (a & b);
            document.write(result);
            document.write(linebreak);
</script>

4-Logical Operators (&&,||,!)

<script type="text/javascript">
         <!--
            var x = true;
            var y = false;
            var linebreak = "<br />";
            document.write("(x && y) => ");
            result = (x && y);
            document.write(result);
            document.write(linebreak);
</script>

5-Assignment Operators (=,+=,-=,*=,/=)

<script>
var x = 10;
x += 4;
document.getElementById("demo").innerHTML = x;
</script>