Characters can be Human, Elven, Dwarven and Halfling, each of which has different characteristics.
There are four class trees to create your characters in - Fighters, Rogues, Clerics and Mages - though as you gain experience, you can grow and customise these to create unique individuals even if they are the same class.
Lets face it, when you're in a pickle at the local dwarven tavern, there's no-one better to have by your side than a big building sized companion with their fists up ready to give a bruising as good as they takes. Skilled in fighting in armor, using shields and there to be the rock upon which enemy breaks, fighters are fantastic and make up a vital part of almost every group of adventurers.
A fighter might be great to have in a group, everyone knows that, but where you really do some damage is if you stick em in the back... or the guts... heck, kick em when they're down... or up for that matter. A rogue will tell you they can do everything a fighter can do, but quicker. And better. Also, why go running at the enemy when you can whip out a trust bow and shoot them from all the way back there.
Ever since ancient wizards shattered the wanderer, religions have sprung up claiming to have the answers to bring the world that was back together, or how to live best in the light of the Gods in the world we have left. Some of these may well hold a grain of truth to them as clerics can indeed perform miraculous healing prayers, invoke the favour of the Gods on the battlefield. Not everyone believes the religions, and some of them seem to completely contradict one another - but best not tell that to the clerics face. You never know when you might need them backing your play.
Every important wizard or always finds a couple of gullible types to wander about with them and offer protection against all manner of tedious things. Luckily your party can do that for your mage if you choose to bring one. Mages harness the immense powers that the celestials wash over the world every moment of every day. A good mage can alter the very reality around them, willing the pure elements to form, channelling powerful energies through the right incantations to raze enemies where they stand, to literally transform reality in ways that benefit the group that no-one else can do.