Saturday Night Live premiered on this date in 1975. It originally was titled NBC's Saturday Night.
It's hard to believe that the show has been around for 37 years! That makes the 25th anniversary video, SNL 25 [DVD SAT] 12 years old, but it's definitely still worth watching, as is Saturday Night Live: The Best of Steve Martin [DVD SAT].
Here's a classic SNL sketch (warning: not for kids); Robert DeNiro is awesome!