It is techinically a two-component spinor, which is why the direction of the spin 'moves' if you measure it along different x,y,z axes. It is also quantized unlike a normal vector: All fermions have quantized half-integer spin magnitudes and all bosons have integer magnitudes.
Magnetic fields can be used to change the spin.
When particles interact, opposing spins tend to pair up in each electron orbital which cancels the magnetic field. This is why permanent magnets must have unpaired electron orbitals.