Gif Central boasts hundreds of funny animated gifs. Only the best of the best make it onto this site, with most of them having an accompanying source. No tumblr-esque one-second-long disappointments. No obscure titles or descriptions.
This is an animated gif from the Sci-Fi movie Scanners (1981), in which a guy's head literally explodes. This gif is typically used as a metaphor for when somebody discovers a bit of information that shocks them.