oh, one thing I forgot about, the radius of the fretboard is usually different between the two. a lower radius, which has a curve in the fretboard, is better for playing towards the headstock, like open chords and stuff, and a higher radius, which is flatter, is better for soloing. usually a 22 will have a lower radius, and a 24 will have a higher one. though, now on some guitars they have it so that it starts out with a lower radius towards the headstock, and flattens out as it get higher up the neck.