Changes in HTML 5 - <img/> Tag

What's new in HTML 5
Differences between HTML 5 and earlier versions of HTML

The following attributes should not be coded on the <img> tag because they either have been deprecated or were never officially supported:

In ployglot HTML documents the <img/> tag is coded as a self-closing tag the same as in the 2000-2010 Recommendations from the W3C HTML Working Group. Those specifications changed the ending delimiter to /> from > in older recommendations. They also defined the HTML namespace for the img element type name and the names of other HTML element types.