why we use return in javascript code example

Example 1: why we use return method

Return method is for to be able to
continue to work what method retrieves. 
For example if it returns a String.
This means that you can use the returned
value in your code for
further processing.I guess good examples
of such methods are "getters".

Example 2: what does return do in javascript

function add(a, b) {
  return a + b; //Return stops the execution of this function
}

var sum = add(5, 24); //The value that was returned got but inside the variable sum