Protect is a Normal type damage-dealing.
Protect protects the user from all effects of moves that target it during the turn it is used, including damage.
This does not include damage inflicted by weather it is vulnerable to, or damage from a status condition that it obtained on a previous turn (as these are not moves that targeted the user this turn). If the user goes last this turn, the move will not be successful.
Protect can be used even if the user is behind a Substitute.
Acupressure, Aromatic Mist, Bestow, Block, Confide, Conversion 2, Curse, Doom Desire, Feint, Future Sight, Hold Hands, Hyperspace Fury, Hyperspace Hole, Mean Look, Perish Song, Phantom Force, Play Nice, Psych Up, Roar, Role Play, Shadow Force, Sketch, Spider Web, Tearful Look, Transform & Whirlwind are the moves which aren't affected by Protect.