There are many different types of bicycle races.

sport	description	Olympics	UCI ProTour	nice videos	near Chicago
[1] Road cycling
Time trial	No drafting (very similar to a triathlon).	yes	yes	[1] [2]	[1]
Criterium	Short (<3miles), sharp corners.	no	?	[1] [2] [3]	[1]
Cyclo-cross	Road bikes, but offroad. Done in the off-season for cross-training.	no		[1] [2]	[1] [2]
[1] [2] Track cycling
Pursuit	Start at opposite sides of the track, and attempt to catch up to the other.	yes		[1] [2]
Sprint	Unusually tactical, bordering on playful. Going slowly and stopping are viable strategies.	yes		[1] [2] [3] [4]
Keirin	2km 6-9 person race. Japanese-originated, one of the four gambling sports there.	yes		[1] [2]
Madison	A six-day race with two-man tag teams.	yes
Tandem sprint	If it's not the gayest thing you've ever seen, it's a very close second. (and this is third)			[1] [2]
Mountain biking
Downhill	Insane.			[1] [2]
Trials	Hop between obstacles. Main rule: don't put your foot down.			[1]