The Wizard is a player character that can cast spells.
Spells are magic created by the character, generally it's
pretty powerful stuff. Bolts of Fire, Summoning a swarm of
beetles, a charm to make someone think you're their friend.
You only get so many spells per day, so make them count.

The fighter is a very fun player character. This person
is most easily described as "the one who hits things".
Now there's a lot more to it than that, you can specialize
in some really interesting ways. But at the core of it,
you beat things up. Whether you use a bow, an axe, your fists
or even just a chair you picked up off the ground, you're
not to be trifled with when you're up in someone's face.

The Cleric is a player character that can cast spells.
Spells are magic created by the character, generally it's
pretty powerful stuff. Healing Light, A protective barrier
around yourself, The power to bring daylight into the
deepest darkness. You only get so many spells per day,
so make them count.