HTML, or HyperText Markup Language, is the standard language used to create Web pages. The latest version, HTML5, adds features for audio, video, graphics and more to support a wider range of web applications that can run across different devices. The HTML5TEST web site will score your browser's support of the various HTML5 features. None are perfect, but of the major browsers Chrome rates the highest and Internet Explorer the lowest. Not surprising given the profit motives of each company.