MINECRAFT

Minecraft has got three different modes you can select:

SURVIVAL: You have to gather resourses to survive. There are also monsters that you need to defeat. Diferent monsters drop different items when defeated.

CREATIVE: You have every single item and block in your inventory, so you can build amazing stuff without having to gather them yourself. You can fly in creative mode. Also you cant die in creative mode.

PEACEFUL: You can also choose peacful dificulty on survival mode. You still have to gather reasourses to survive, but there are no monsters.

HOSTILE MOBS:

A hostile mob is the name for a monster. Here are some of them:

Creeper: Attacks by blowing up. If you're close enough, you will die.

Zombie: Walks towards you with his arms out stretched. It will hit you causing damage.