Hiding is a game mechanic for the game Five Nights at Treasure Island: Found introduced in the remastered version. As revealed in AnArt's files, it was going to be in the original demo but a memory leak with Gamemaker preventents the source code that includes this to build.
Holding SHIFT allows the player to hide under the desk in The Office until a Suit leaves The Office. A message will appear at the bottom of the player's screen that explains to hold shift to hide. Hiding for too long will cause Slester to jumpscare you.
Hiding is the main mechanic of avoiding Jeff The Killer.
The player can enter hiding by pressing SHIFT, which will 100 percent work against Jeff, however, if the player stays under the desk for too long, then their Dread bar will then go down.