Continents has two types of classes, fighting classes and trade classes.
The classes players can be are:

   a combination type --
      pick one from each column:

        primary or  |   secondary
        fighting    |   or trade
        Warrior     |   Supplier
        Thief       |   Wright
        Cleric      |   Smith
        Mage        |   Traveler
                    |   Alchemist/cook

   so a char could be class Mage/Smith or Thief/Wright or
   Warrior/Smith or Mage/Traveler or Warrior/Supplier,
   and so on.

   or a single type only
   -- Paladin, Ranger, Ninja, or Trader.

   Paladin, Ranger, Ninja, and Trader are specialized
   classes already containing skills from 2 or more other
   types and/or having special skills and do not get to
   choose a second class type to be.

The trade types may only be selected as a secondary class,
except for Trader, a special case business only class.
Traders have some of the skills of the other trade
classes, many specialized skills, and no fighting skills.