hi, i am trying to work out exactly what is the difference in quantum mechanics between 1) spin, as in 'angular momentum' and 2) spin as in 'quantum spin number'. It seems like quantum spin number only describes certain properties, like whether a particle is a fermion or a boson (so it wouldn't make any difference if we labelled different 'spins' 'apples' and 'pears' rather than '1,2,3' or '1½,2½,3½..') while angular momentum seems to be a relative physical quantity -- i.e. a particle with angular momentum, say 3, has 'higher' angular momentum than one with angular momentum 1, and one with angular momentum 2 is somewhere imbetween. Is that correct? From what I've read some sources seem to say these two values are independent. Elsewhere I've heard that quantum 'spin number' is actually just the z-component of the angular momentum of the particle, and the spin number is a way of describing the way the particle is actually physically spinning. Any clues?