Running events include sprints, middle-distance and long-distance races, relays and hurdles. Each event listed here may not be available at each meet, and some events may be unique to certain genders and/or age groups.  Typically, sprinters (and sometimes certain middle-distance competitors) run timed preliminary races, called heats. The top times qualify to move on to the finals of that event. Runners always circle the track counter-clockwise.

 Sprints

100 meters - 1/4 of the track (one of the straight sides); .0625 miles.
200 meters - 1/2 of the track; .125 miles.
400 meters - One lap around the track; .25 miles.

Middle-Distance

800 meters - Two laps around the track; .5 miles. 
1500 meters - Three and three-quarters laps around the track; .94 miles. (At most high school meets, this race is replaced by the 1600 meters, which is equivalent to 1 mile.)

Long-Distance

3000 meters - Seven and one-half laps around the track; 1.9 miles. (At most high school meets, this race is replaced by the 3200 meters, which is equivalent to 2 miles.)
5000 meters - Twelve and one-half laps around the track; 3.1 miles.

Relays

4x100 meters (aka 400 meter relay) - Four athletes running 100 meters each.
4x200 meters (aka 800 meter relay) - Four athletes running 200 meters each.
4x400 meters (aka 1600 meter relay) - Four athletes running 400 meters each.
4x800 meters (aka 3200 meter relay) - Four athletes running 800 meters each.

Hurdles

80 meters
100 meters
110 meters
200 meters
300 meters
400 meters

Steeplechase

2000 meters - Athlete encounters barriers and water jumps throughout the race; 1.25 miles.

Race Walking

1500 meters - Three and three-quarters laps around the track; .94 miles.
3000 meters - Seven and one-half laps around the track; 1.9 miles.
5000 meters - Twelve and one-half laps around the track; 3.1 miles.