Passive is a behavioral game mechanic applied to various Mobs in Minecraft.
Unlike Neutral or Hostile mobs, passive mobs will never attack a player or another mob, even when they are attacked themselves. When under attack, a passive mob will typically try to run away from their attacker in a random direction. Examples of mobs with this behavior include Polar Bear cubs, and Rabbits.
Some mobs are always passive, regardless of which Game Mode is being played. However, all mobs, including some neutral and hostile mobs, become passive toward players when the difficulty is set to "peaceful", or when playing Creative mode; however, when the difficulty is set to "peaceful", most hostile mobs will not spawn.There will be an exception in some neutral mobs,as they can still attack a player when provoked (Some examples are Wolves,and Polar Bears),but they will deal no damage whatsoever,much like how a small slime attacks.