The document discusses linking and hyperlinks in SMIL (Synchronized Multimedia Integration Language). It covers: - The SMIL 2.0 linking module defines the <a> and <area> elements for creating hyperlinks, similar to HTML. - Hyperlinks only work with clip source tags and multiple <area> elements can link different parts of a visual clip. - Attributes like href, begin, and end are used to define links and link activation times. - Links can be used to move within a SMIL presentation timeline or link to other presentations. - The <area> element can define "hotspots" over images or videos to create interactive regions.