HTML5
HTML5 represents a radical departure from the tradition of HTML. In all previous HTML specifications, the descriptions stopped short of describing any JavaScript interfaces, instead focusing purely on the markup of the language and deferring JavaScript bindings to the DOM specification.
The HTML5 specification, on the other hand, contains a large amount of JavaScript APIs designed for use with the markup additions. Part of these APIs overlap with the DOM and define DOM extensions that browsers should provide.
Class-Related Additions
One of the major changes in web development since the time HTML4 was adopted is the increased usage of the class
attribute to indicate both stylistic and semantic information about elements. This caused a lot of JavaScript interaction with...