What are the different bra sizes?

Numbers start from 28, upwards to a possible 56 (in some American brands) there are apparently some 26 Bras around (which I've yet to find, but believe it or not quite a few adult women are 26) and cup sizes go from AAA (I don't know what this stands for though...) AA, A, B, C, D, DD(While AA is smaller than A, DD is bigger than D) sometimes the letters change here though, an E in one shop may be a DD in another, and still others do DDD, rather than or before E/F. Generally though it is C, D, DD, E, F, FF, G, GG, H, HH, I, J, JJ, K.