What does a comma do in JavaScript expressions?

Question

If I use:

1.09 * 1; // returns \"1.09\"

But if I use:

1,09 * 1; // returns \"9\"

I know that 1,09 isn\'t

Answer 1

Have a look here - the comma stands for multiple expressions / statements. For example in your code you could use a line like this:

var a=0, b=0, c=0;

This would declare all three variables without writing:

var a=0;
var b=0;
var c=0;

Hope that helps.