The Unary Negation Operator is used to convert the operand into a number. After that it negates.
Example
You can try to run the following code to learn how to work with Unary Negation Operator in JavaScript −
Live Demo
<html>
<body>
<script>
var a = true;
var b = '0xFF';
var c = "false";
var c, d, e;
var linebreak = "<br />";
c = -a;
d = -b;
e = -c;
document.write("-true = "+c);
document.write(linebreak);
document.write("-'0xFF' = " +d);
document.write(linebreak);
document.write("-false = " +e);
</script>
</body>
</html>