It’s quite difficult to come up with a complete A-to-Z series of posts because not quite all the letters of the alphabet offer suitable material.
In UK English we use the word quite as an adverb to mean “completely” and we also use it to mean “to a certain extent”.
The meaning is usually quite clear from the context. But not always. In the foregoing sentence it could be either. So it’s quite important to be sure you know which meaning is intended.
The word can also be an exclamation expressing agreement or understanding.
You can read about the correct use of the word quite and a whole lot more, in the English Digital Content style guide.