HTML Best Practices: Type attribute on script and style elements is not necessary in HTML5

Since all browsers expect scripts to be JavaScript and styles to be CSS, you don’t need to include type attribute. While it isn’t really a mistake, it’s a best practice to avoid this pattern.

Bad example:

<link type="text/css" rel="stylesheet" href="css/style.css" />
<script type="text/javascript" src="script/scripts.js"></script>

Good example:

<link rel="stylesheet" href="css/style.css">
<script src="script/scripts.js"></script>