They are objects that help you with thrusting using space bar.
Learn to Fly
It costs 250$. It has the lowest boost power.
Its costs 2000$ it is a bit faster.
It costs 10000$ and is the best rocket in the game.
Learn to fly 2
Costs 100$ it is very slow boost.
Costs 250$ it is pretty slow but now a lot!
Cost 1000$ it speed is moderate.
Cost 10000$ It has meduim speed!!
Cost 35$ it thrust its the most slighty of the boost (or rockets)
Cost 800$ Small delay before it goes
Cost 9500$ Fastest non omega booster
Cost 175$ 4 weak boosts