Most important thing about HTML 5 is that its now no longer part of SGML but its a language of its own. A number of new elements added as well as others removed or deprecated.There are lots of new features that requires a detailed article but here I am trying to focus on major ones.

1. First of all simplified doctype for html 5 is:
<!doctype html>
2. For the purpose of drawing graphics, new canvas element has been added.
<!doctype html>
2. For the purpose of drawing graphics, new canvas element has been added.
3. New Structural as well as Media elements has been added.Structural -> Article, Command, Dialog, Summary, Progress etc.
Media -> Audio, Video, Track, Source etc.4. A number of new form elements has been added as follows:
Media -> Audio, Video, Track, Source etc.4. A number of new form elements has been added as follows:
- datalist
- datetime
- keygen
- output
- datetime-local
- date
- month
- week
- time
- number
- range
- url
5. A number of existing elements has been deprecated or removed. Most important is Iframe removal.
- frame
- frameset
- noframes
- applet
- big
- center
- basefont
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