If a zombie gets close enough to the player, it will start following them until it starts causing damage. This isn't too much of a problem since they walk fairly slow and they have 20 health points (10 hearts). They are able to jump about 2 blocks high, like the player.
When a zombie comes in contact with light from the sun, they will catch on fire and take damage. It is a good idea to wait until morning to hunt for zombies because they will already be taking damage from the sun. Besides spawning randomly, zombies will also spawn from monster spawners, making mob spawners a convenient way to get their drops.
|16||Slay a Zombie.||Kill a zombie.|