Zombie

Zombies are undead hostile mobs that were added in Update 0.3.0. They usually spawn in groups of three. They also burn in sunlight, taking fire damage every second unless they are in water.

Offense
Zombies can pursue any players in a 40-block radius and will attack by swinging their arms. They deal more damage when injured, and will set other players on fire if they are on fire. On Hard difficulty, Zombies can to break down Wooden Doors.

Equipment
Zombies have a chance of spawning with Armor and/or Weapons. This makes them stronger and if they have armor they will not burn in sunlight.

Villagers
Zombies will pursue and try to kill any Villagers in a 40 block radius. If a zombie kills a villager in Hard difficulty, the villager will turn into a Zombie Villager.

Combat
Zombies are easy to kill with a sword, preferably stone or above. A Bow & arrow can also be used when fighting large groups of zombies. It is also effective to use splash potions of healing to kill large groups.

Baby Zombies
Baby Zombies are variants of Zombies that have a 5% chance to spawn in place of any regular zombie. They run faster than the player, and do not burn in sunlight. It makes them more deadly.

Baby Zombies have a 15% chance of spawning on an adult Zombie, a Spider, a Chicken, a Cow, an angry Wolf, a Pig, a Sheep or an Ocelot as a Jockey.

Trivia

 * After fire was removed in 0.3.0 due to bugs, they emitted smoke and received damage until they died.
 * However, since fire was added back, both Skeletons and Zombies burn in daylight.
 * Zombies will always drop the item/armor they have equipped. The chance that they will drop their weapon/item in their hand is smaller.
 * Zombies will not burn when standing in shade or in water.
 * Zombies have the same face as the player's default skin, except recolored green and black.
 * In MCPE Lite, Zombies are presently the only hostile mobs.
 * Before Update 0.11.0, Zombies drop Feathers instead of Rotten Flesh.
 * Zombies can pick up certain items, and wear armor.
 * If a Zombie wears a helmet, it will not burn in daylight. However, the helmet will decrease in durability.