Whilst we see, read and hear a lot about the new semantic elements in HTML5 we arguably hear far less about the application programming interfaces (APIs) that make up a large part of the specification itself.
As I'm sure you're aware that there are two versions of the HTML5 specification, one published by the W3C and another by the WHATWG. The living HTML specification maintained by the WHATWG contains additional APIs to those in the W3C HTML5 spec (although generally they are also maintained by the W3C but in separate specifications).
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