how to send an alert in javascript
//you can either do this:
function mousePressed() {
	//you can have any message
  alert("I'm the best");
}
//or you can do this:
function keyPressed() {
	//you can do any key
  if (keyCode === UP_ARROW) {
  	//and any message
    alert(number = random(0, 500));
  }
}
//or you can do an (if) statement
if(x > width) {
 	alert("yay you did it");
}