What is a GIF?
First introduced by Compuserve in 1987, the Graphics Interchange Format (GIF) is one of the most common formats for animated images. Today the format has been eclipsed by the near-universal support for Flash and PNG, but during the 1990s and early 2000s GIFs were a defining component of the Web. GIFs have a multitude of meanings: for Internet nostalgists, they tie into the DIY aesthetic of the Internet before the general turn to modernist web design and free professional CMSes like Wordpress, Moveable Type, and Tumblr; for open-source advocates, they represent a certain form of tyranny colored by Compuserve's fight, in the mid-1990s, to require licenses to display GIFs; for artists, they represent the most immediate, reproducible, and, in many cases, visually specific animated medium available. A good general description of the GIF and its history can be found on Wikipedia, while Duncan Alexander's essay on the topic addresses the particulars of the medium with regard to artists.