User blog comment:Nabukun/Anyone reading Japanese here?/@comment-1739368-20160412060511/@comment-27659575-20160414123142

What I can understand that it's some sort of rough classification of Stands.

A B & B' designate range?

a ab b designate a type of ability?

And Araki sorta classes Stands like this: for instance Purple Haze was A/a, Star Platinum A/ab, Sheer Heart Attack B'/a...