In addition to the distinction that frequency is an objective measure and pitch is a subjective one, it's also useful to note that the pitch of a note may not be directly related to any easy measure of frequency.
Case in point: a bell, tuned to A440, will generally emit sound energy at roughly 880Hz, 1320Hz, 1760Hz, etc. -- in other words, for a pitch frequency $f$, a bell gives you $n\,f$ for $n \in \lbrace 2, 3, 4, \cdots \rbrace$. It does not give you the fundamental -- and yet, when you hear a bell, you hear the pitch corresponding to the fundamental.
This happens because our hearing is optimized for an environment where all of the "musical tones" that we hear (and that we need to hear to understand speech and other utterances) are more than just a pure sine wave.
The wider study of this sort of phenomenon is called "psychoacoustics", if you want to search for it.