I BSing with a few instructors the other day and we got to talking about one of the reasons a student of his was busted on his CFI ride. The question was how many and what types of turbulence are there. I do not know the answer the candidate gave, but what the examiner was looking for perplexed us. He said there were three types; weather, mechenical and pilot induced. I get weather and mechenical, but pilot induced turbulence. Anyone have any insite?