JFK
November 22, 1963, United States President John Fitzgerald Kennedy was assassinated.
There is an ample amount of sites dedicated to the assassination of JFK, so it's not totally neccessary to reiterate. Here are links to good JFK sites.
The John F. Kennedy Assassination Homepage
The Kennedy Assassination
Yahoo's JFK Directory
If interested in the Zapruder film, here are some other links
Bob Cornell's Zapruder Gallery
(Warning: Not all content on Bob Cornell's Zapruder Gallery is particularily tasteful.)