The Rest Is History

Looking at the rest of our starting template, we have the usual body element along with its closing tag and the closing html tag. We also have a reference to a JavaScript file inside a script element.

Much like the link tag discussed earlier, the script tag does not require that you declare a type attribute. If you ever wrote XHTML, you might remember your script tags looking like this:

<script src="js/scripts.js" type="text/javascript"></script> 

Since JavaScript is, for all practical purposes, the only real scripting language used on the Web, and since all browsers will assume that you’re using JavaScript even when you don’t explicitly declare that fact, the type attribute is unnecessary in HTML5 documents: 

<script src="js/scripts.js"></script>  

We’ve put the script element at the bottom of our page to conform to best practices for embedding JavaScript. This has to do with the page-loading speed; when a browser encounters a script, it will pause downloading and rendering the rest of the page while it parses the script. This results in the page appearing to load much more slowly when large scripts are included at the top of the page before any content. It's why most scripts should be placed at the very bottom of the page, so that they’ll only be parsed after the rest of the page has loaded.
In some cases, however, (such as with the HTML5 shiv) the script may need to be placed in the head of your document, because you want it to take effect before the browser starts rendering the page.