HTML and CSS Reference
A URI value ( <uri> ) is a reference to a file such as a graphic or another style sheet. CSS
defines a URI as relative to the style sheet that contains it. URI stands for Uniform Resource
Identifier, which is the more recent name for URLs. (Technically, URLs are a subset of URIs.)
In CSS, which was first defined when URIs were still called URLs, this means that references
to URIs will actually appear in the form url(<uri>) . Fun!