What does the ^ (caret) symbol do in JavaScript?

I have some JavaScript code:

<script type="text/javascript">
$(document).ready(function(){
  $('#calcular').click(function() {
    var altura2 = ((($('#ddl_altura').attr("value"))/100)^2);
    var peso = $('#ddl_peso').attr("value");
    var resultado = Math.round(parseFloat(peso / altura2)*100)/100;
    if (resultado > 0) {
      $('#resultado').html(resultado);
      $('#imc').show();
    };
  });
});
</script>

What does the ^ (caret) symbol mean in JavaScript?

The ^ operator is the bitwise XOR operator. To square a value, use Math.pow:

var altura2 = Math.pow($('#ddl_altura').attr("value")/100, 2);

^ is performing exclusive OR (XOR), for instance

6 is 110 in binary, 3 is 011 in binary, and

6 ^ 3, meaning 110 XOR 011 gives 101 (5).

  110   since 0 ^ 0 => 0
  011         0 ^ 1 => 1
  ---         1 ^ 0 => 1
  101         1 ^ 1 => 0

Math.pow(x,2) calculates x² but for square you better use x*x as Math.pow uses logarithms and you get more approximations errors. ( x² ~ exp(2.log(x)) )

This is the bitwise XOR operator.

Its called bitwise XOR. Let me explain it:

You have :

Decimal Binary   
0         0
1         01
2         10
3         11

Now we want 3^2= ? then we have 11^10=?

11
10
---
01
---

so 11^10=01 01 in Decimal is 1.

So we can say that 3^2=1;

> The bitwise XOR operator is indicated > by a caret ( ^ ) and, of course, works > directly on the binary form of > numbers. Bitwise XOR is different from > bitwise OR in that it returns 1 only > when exactly one bit has a value of 1.

Source: http://www.java-samples.com/showtutorial.php?tutorialid=820