The document referenced by the src attribute may be any valid HTML document or displayable object, including images and multimedia. In particular, the referenced document may itself be composed of one or more frames. The frames are displayed within the referencing frame, providing yet another way of achieving complex layouts using nested frames.
Since the source may be a complete HTML document, all the features of HTML apply within a frame, including backgrounds and colors, tables, fonts, and the like. Unfortunately, this also means that multiple frames in a single browser window may conflict with each other. Specifically, if each nested frame document (not a regular HTML document) has a different