I will add the most important new HTML5 tags.
1. <A>: Use to create links in content.
2. <ABBR>: Works in a similar way to <dfn> and <acronym>, using a title attribute
3. <ADDRESS>: Not commonly used. Recommend looking into microformats, which allow for more detail and interoperability.
4. <APPLET>: The old way to insert a Java app. Use <object> instead today.
5. <AREA>: Avoid image maps where possible. Occasionally necessary.
6. <BODY>: Essential (unless you’re using frames)
7. <BUTTON>: Often better than <input type=”button” /> or <input type=”submit” />, as it allows you to assign different styles based on the HTML element alone, whereas differentiating style based on the type of input is less well supported.
And so many tag are included in HTML.