All monsters on Minecraft
The term "Mob" is short for "mobile" and has been used as a general term referring to any moving entities in games since the first MUDs surfaced.
There are currently 25 different mobs in Minecraft: Xbox 360/Playstation Edition, excluding the Player.
Passive mobs will never attack the player. All passive mobs require land and light to spawn on. However, the squid are the only mob that require water to spawn (unless spawned using Spawn Eggs).
Neutral mobs will not attack the player unless provoked. The act of provoking neutral mobs varies between mobs.
Hostile mobs will attack the player when in range. Zombies, Creepers, Skeletons, and Spiders require a light level of 7 or less to spawn. All mobs' hostility levels are based on how they are spawned by default. Spiders may become neutral, but they do not spawn neutral.