Q: and what's a quarter note and a whole note?
A: in most cases, a quarter note is 1 'beat' worth of time. a beat is typically the length of time that would recieve one foot tap, if you are foot tapping. in the normal time-signature (4/4) a quarter note is one beat. the 4/4 time signature is so normal that the quarter note (and thus all the notes) have been named in relation to a bar of 4/4. a quarter note is a quarter of the length of a bar in 4/4. and a whole note is the length of 4 quarter notes. in different time signatures, with different bar lengths, these names don't actually relate to the bar. the names are kept as if they are relating to a 4/4 bar, just because that's their name. at that point it's just a name