HTML is a key part of the Internet. It has a short but extremely vibrant history. In order to understand what HTML5 is about, it’s useful to look at where it came from. The Internet (and the Web in particular) has been changing at a dizzying pace. HTML has been trying to keep up.
When HTML was first devised, it comprised a handful of tags, and HTML did little more than determine how a page was laid out. As the Web matured, many features were added. Today’s Internet is still about documents, but it’s also about applications. Today’s Web sites are dynamic interactive applications.