Speed picking is when u wiggle the pick really quickly on a string, it is really fast.Good examples of speed picking is by a band called DreamTheater.Their album "Metropolis Part 2 : Scenes from a Memory" is not only an incredible album, but alos has great solos from all instruments including synthesiser. The solos are difficult but are great examples of speed picking in practice.

Good Luck and hope this was of help!