Mechanics work in automobile workshops and they fix cars.
Not everyone can be a good mechanic, you need to be good with your hands and smart enough to understand how complicated machines work.
Among other things a mechanic must know how engines, braking systems and clutch systems work.
Really good mechanics are able to change entire car engines within a few days.
Mechanics also help you to do maintenance on cars. This helps to prevent cars from needing repairs.
If you want to be a mechanic, you have to be comfortable working in hot and greasy workshops.
Mechanics also work on airplanes, space ships, boats and motorcycles.