HTML5 was designed to replace HTML 4, XHTML, and the HTML DOM Level 2. The key goals and motivations behind the HTML5 specification were to:
Deliver rich content (graphics, movies, etc.) without the need for additional plugins, such as Flash.
Provide better semantic support for web page structure through new structural element tags.
Provide a stricter parsing standard to simplify error handling, ensure more consistent cross-browser behaviour, and simplify compatibility with documents written to older standards.
Provide better cross-platform support whether running on a PC, Tablet, or Smartphone.
