hello,
I have seen this question many times hopefully I can clear it up.
App. skills 1-3... are equalvilant to lets say, an Apprentice, which means someone still learning aka a student.
Adept skills 1-3... are the same as someone who has become proficien/or skilled in the certain art.
Master skills 1-3... are self explainitory, obviously they mean you have mastered the skill but just like in Martial arts there are different lvls to a black belt rank
in other words you could compare them to lvls of education
App skills 1-3 would be Middle/junior high school
Adept skills 1-3 would be High school
and Master skills 1-3 would be college/university's
hope this helps lol
peace