To float nice and steady down off of an air plane, also used for dropping off packages from a plane, or can possibly be used for the US Army! Other-wise we would get crushed by the intense force of gravity. Well put, no?
It can have many purposes, but the main reason is to slow something down. Be it a skydiver, or a care package, or a drag racing car, or a space shuttle. It slows things down.
How a parachute works
It's pretty simple really. As the parachute gets pulled downward by the weight of the person/object tied to it, air gets trapped in the parachute and creates drag (also known as resistance), which counteracts the effects of gravity - and this slows down the speed at which the parachute (and anything that is attached to it) will fall.
Where did the word parachute come from?
Here's something you might not have known:
Although Leonardo Da Vinci is credited for designing the first parachute, the first successful model and jump was completed by a Frenchman.
That's why the French words para (against) and chute (fall) were combined to give the parachute its name: the "against fall".