[Back In The Saddle]

Just to be absurdly clear...

There is no signal specifically for hooking (though as BBR mentioned, the NFHS is apparently considering one), for hooking we're normally going to use the PC signal if it's the ball-handler that hooks, the team control signal if it's a non-ballhandler offensive player, or a hold signal if it's a defensive player or there is no team control. With the PC or TC signal, some officials will also give an unofficial "hook" signal to communicate the nature of the foul (which is sometimes not obvious). This is against NFHS guidelines and should only be done if it's deemed acceptable in your area.

Displacement is a foul, whether it's on-ball or away from the ball. Now we could get into a good discussion about what is displacement v. incidental contact v. two players, neither of whom has "position", who are jockeying for position. But if the official deems that a player has, in fact, been displaced, it's a foul.