"Quite" is an adverb that means something similar to "very". It's perhaps a little lower in strength than "very".

If you're using "quite" with an adjective, you say "quite ___":

I'm quite hungry.

If you're using it with a noun, you say "quite a ___" or "quite an ___":

It's quite a useful book.

You have quite an impressive background.

"Quite" is an intelligent- or sophisticated-sounding word. Some people who want to seem intelligent use "quite" more, while people who want to seem more "down to earth" use other words like "really ___" or "real":

You must really have a sense of accomplishment.