55m-Only happens at indoor tracks because the straightaway is shorter, the shortest event of them all.
100m-Sprint one straightaway on the track, the shortest outdoor event.
200m-One curve and one straightaway all out sprint
400m-One lap sprinting as fast as you can
800m-Two laps round the track, basically a long sprint
1600m-4 laps around the track
3200m-8 exciting laps around the track, the longest of all events
4x100m-4 people each sprinting 100 meters a piece
4x200m-4 people each sprinting 200 meters a piece
4x400m-4 people each sprinting 400 meters a piece
4x800m-4 people each running 800 meters a piece
4x1600m-I've heard this relay exists at some meets, 4 people each running 1600 meters a piece
4x3200m-No such thing, it would take forever!
100m hurdles girls-One girl sprinting one hundred meters jumping the hurdles as they come
110m hurdles boys-One boy sprinting 110 meters and jumping the hurdles as they come
300m hurdles-Boy or girl sprinting 300 meters and jumping the hurdles as they come