If you're not quite sure exactly what cymbal does what, there are a few different choices.
Firstly, Hi Hats are the pair of cymbals that sit together on one stand, with a pedal opening them. Usually, these are the standard cymbals a drummer will play on the beat and are used for standard patterns, rather than accents.
Crash Cymbals are the standard most people think of when it comes to the cymbal sound. They are explosive, loud, in your face and are used for the most common accents.
The Ride Cymbal is usually the largest cymbal on a kit and can produce a lot of different sounds based on where it is hit. The bell, at the top of the cymbal, can produce a sharp ping sound, whereas the Large outer curve can produce long sustaining shimmer, even changing tone depending on how far in you hit them.
Chinas have an upturned edge, and whilst they produce a loud explosion of sound like a crash, their tone sounds more obtuse, like hitting a large metal plate. Their design can be traced to Chinese gongs, hence the name
Splash cymbals are used a lot like crashes, for accents, but they sound small, thin, and short, just like a water splash.