Text-level

U

The u element represents a span of text with an unarticulated, though explicitly rendered, non-textual annotation (when you are annotating something, but not explicitly saying what it is). Examples include indicating misspelt words, labeling proper names in traditional Chinese prose, or indicating a family name when the name’s order is non-western. http://dev.w3.org/html5/spec/Overview.html#the-u-element