The Apple Keynote Event (also the SteveNote and the Apple Event) are the presentations Apple gives to the press, usually two to three times a year. Often, Apple will announce new products and give new statistics for Apple inc. An example of a Keynote was the March 7th, 2012 Keynote where Apple announced the iPad 3 .
One More Thing
At a typical SteveNote, Steve would often walk out of the stage but before officially leaving walk back and announce one more thing. An example of a product announced by a One More Thing are color iMacs in 1999, the iPod Shuffle in 2005, FaceTime for iPhone in 2010, and the most recent, iTunes Match in 2011.