Ghost prevents players from appearing on radar while an enemy Spy Plane is active and allows wearing Ghillie Suits in multiplayer without using sniper rifles.
Pro effect
Ghost Pro prevents automated killstreaks (except Attack Dogs) from attacking the player, removes red targeting boxes for player-controlled killstreaks, hides the player from infrared scopes and camera spikes, prevents Tactical Mask Pro from revealing the player's location, and removes the red crosshair and name when enemies aim at the player.