What does drafting mean in cycling?

Answer 1

Cyclists draft because when they ride behind someone the wind resistance is lessened therefore the cyclist has to exert less energy to overcome the wind resistance, which will help them maintain their endurance for a better ride.

Answer 2

Its the same thing car racers talk about, and it boils down to science. Riding behind another vehicle, a bike in this case, eliminates much of the drag that you would otherwise face head-on. You can hide in their trail, avoiding wind resistance from the air, and go faster.