title: Load JavaScript dynamically
body: <p>I have a web page and a canvas with Google Maps embedded in it. I am using jQuery on this site.</p>
  
  <p>I want to load Google Maps API only if the user clicks on "Show me the map". Further, I want to take away the whole loading of the Google Maps from the header in order to improve my page performance.</p>
  
  <p>So I need to load JavaScript dynamically. What JavaScript function I can use? </p>