In music what's the difference a between note and a key?

Answer 1

On a piano, a key is the thing you press down with your finger. A note is what you hear with your ear. The note is also what you see on your sheet music. Also, on the piano, you will notice you have a pattern of 3 white keys and 2 black keys, followed by 4 white keys and 3 black keys. If you start at middle C and play 8 notes, that is also a key. That is called the key of C. That tells which set of notes are normally used when playing a piece of music. So the term key can mean two different things. If someone says, "This is in the key of C," it does not mean the only note you hear will be a C. You will hear many different notes.

Answer 2

Yes; the only notes are A B C D E F G. Their pitch will change depending on the key, but the notes stay the same.