Javascript Math dist( point1, point2 )

function dist( point1, point2 ){
  
  var xs = 0;/*  w  ww . ja  va 2 s. c  o  m*/
  var ys = 0;
  
  xs = point2.x - point1.x;
  xs = xs * xs;
 
  ys = point2.y - point1.y;
  ys = ys * ys;
  
  return Math.sqrt( xs + ys );
}