Its everyones least favorite mob: creepers. They are the most known mob in minecraft, and the most destructive.

Ups: they give you gun powder which can be made into TNT.

Downs: they explode when in range, which can destroy your house and everything around it.

When fighting creepers use a bow instead of a sword, because they will explode when you get close they hiss and then explode. If a creeper ever spawns in your house, try to lead it out or snipe it with a bow and arrow. Also when creepers explode, they don't give gunpowder.