title: how to call onclick on an external JS file? w/o jquery
body: <p>I'm working on some web very simple drag and drop game using html5 and javascript. After they drag the elements I have a button that verifies either the arrange is correct or not. My verify function is on an external JS file and I'm calling it using onclick inside the input tag. It works, however my boss doesnt want event handlers to be shown on the html. I'm just starting with javascript so is there a way to call an onclick event without using the onclick on a tag in the html file? </p>
  
  <p>Ive read you can do it easily with jquery, but can you use it without jquery?</p>