Some fouls carry some extra provisions, as listed below.
Strip: If a foul causes a player to lose possession of the disc, it is a strip. A strip is a subset of fouls and is treated the same way.
Initiating contact with a disc in a player's possession is a foul.
Sustained contact with, and control of, a non-spinning disc is required to establish possession (3.J). A player may not call a strip if they had only momentary contact with or lacked control of the disc at the time of an opponent contacting the disc because the player did not have possession.