Warrior / Gladiator
Warriors live for combat and the thrill of battle. They are the best fighters of all the classes, but lack the subtle skills of thieves and the magical talents of mages and priests. Warriors are best for those who don't mind taking the direct approach, even when another method might be called for.
Alchemist / Scientist
Alchemists are the tinkers of the lands, not content with how things ARE, always seeking to improve on what nature has made. There were no alchemists until recently, when the gods walked again on the lands, but there have been strides made to harnessing chaos properly so the study of alchemy is not as dangerous to the student.
Cleric / Priest
Clerics are the most defensively orientated of all the classes. Most of their spells focus on healing or defending the faithful, with their few combat spells being far less powerful than those of mages. However, clerics are the best class by far at healing magics, and they posess an impressive area of protective magics, as well as fair combat prowess. Clerics are allowed only the use of blunted weapons, because of their vows.
Druid / Sage
Druids are the protectors of nature. Some spend their lives in forests, others in deserts, and some still in seas or mountainous regions. Where a druid can be closer to nature and life than to the constructs of mortals, that druid can be happy. Because they are so in tune with nature, nature's magics come naturally and strongly to them.
Knight / Paladin
Knights are the mounted warriors of the realm, wearing the heaviest armors and mounted on specially trained steeds, who can be made to aid the knight. Able to rally others to his causes, the knight is a natural leader. Knights also tend to show little fear, often fighting more and more fiercely as the fight goes on and they take more and heavier wounds. There were no real knights in the realms until quite recently, but the ones who have appeared seem to take great pride in seeing justice done.
Mage / Wizard
Mages specialize in the casting of spells, offensive ones in particular. Mages have the highest-powered magic of any class. They are also very skilled at the use of magical items, though their combat skills are the weakest of any class.
Necromancer / Vivimancer
Necromancers are mages of the undead. Opposite to clerics, necromancers are often seen as corrupt and evil, though that is not always the case. Able to turn the forces of death and decay to their will, necromancers have strong magics that can confound and confuse a soul at the most primal level.
Ranger / Strider
Rangers are travelling woodsmen, usually solitary and aloof. They are often the protectors of those far from home, travellers who are lost, or even bounty hunters who track criminals in order to bring them to justice or just to make a buck. They are sometimes used as scouts for armies, and sometimes make up their own force in times of war. Rangers may not have the pure combat effectiveness of warriors, but they have skills and abilities that no warrior possesses, including the ability to shoot a bow and find things hidden where most would miss them.
Thief / Mercenary
Thieves are specialists at thievery and covert actions, being capable of entering areas undetected where more powerful adventurers would fear to tread. They are better fighters than clerics, but lack the wide weapon selection of warriors.