Mechanics is the branch of physics that studies how things move and what forces cause that movement. When scientists figure out why a ball curves when you throw it with spin, or why a heavier sled goes faster down a snowy hill, they're using mechanics.

Isaac Newton founded modern mechanics in the 1600s when he discovered his famous laws of motion. These laws explain everything from why you lurch forward when a car stops suddenly, to how rockets can fly to the Moon. Engineers use mechanics to design bridges that won't collapse, cars that handle curves safely, and roller coasters that thrill riders without throwing them off the track.

The word also refers to the practical details of how something works. When your teacher explains the mechanics of long division, she's showing you the step-by-step process. A coach might work on the mechanics of your swimming stroke: the exact way you move your arms, kick your legs, and turn your head to breathe. Getting the mechanics right often makes the difference between struggling and succeeding.

A mechanic is someone who repairs machines, especially cars. Good mechanics understand both the theory of how engines work and the practical skills needed to fix them. They can hear an odd sound and know exactly which part needs attention.