http://www.kingdomofloathing.com/maint.php is a fun website for young adventurers to try on and maybe get hooked up on it.
Classes
Players in the game choose from a number of classes when they sign up for an account:
Seal Clubbers - "Seal Clubbers hail from the frigid Northlands, because one character class always hails from the frigid Northlands. They rely on their Muscle to survive."
An offensive class, with skills that expand their fighting style and help them in combat.
Turtle Tamers - "The Turtle Tamer's mystical connection with his terrapin brethren imbues him with great power. He excels at moving very slowly and winning footraces with smug satisfaction. His Muscle is the key to his success, and to his long lifespan."
A defensive class, with their skills complimenting their defense and the ability to summon turtles to do their dirty work in battle.
Pastamancers - "With his mastery of the arcane secrets of Noodlecraft, the Pastamancer is a force to be reckoned with. He relies on his Mysticality to get ahead in the world."
A crafting/offensive class, with skills to make some of the best foods in the game and very powerful combat spells.
Saucerors - "Long engaged in an uneasy truce with the Pastamancers, the guild of Saucerors protects the secrets of the Ancient Brotherhood of Gravymakers. Their Mysticality is their most important attribute."
A crafting/defensive class, with skills to make powerful stat-boosting potions as well as casting buffs (shields in the form of Saucespheres) on themselves and other players.
Disco Bandits - "The Disco Bandit boogies to and fro, hither and yon. Whence comes he? No man knows. Whither strikes he next? All men live in fear of him and his Moxie."
A defensive/crafting class, with very high Moxie (and thus very high evasion) as well as the skills needed to make very potent booze.
Accordion Thieves - "The scourge of mariachis and polka bands, the Accordion Thieves have plied their malign craft since time out of mind. Their Moxie serves them well in both their adventures and their interactions with 'the ladies.'"
A defensive class whose skills are all buffs, providing a vast variety of boosts to himself and/or other players.
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Attributes
Each player has three major attributes. Also, each class specializes in one of the attributes, and raising that special attribute sufficiently results in gaining a level:
Muscle - determines hit rate, or Dexterity in mainstream RPG's, and the maximum HP of a character - Seal Clubber and Turtle Tamers specialize in Muscle. A minimum amount of muscle is also required to equip non-ranged weapons and a few hats.
Mysticality - determines the damage of certain skills, mostly magic spells, and the maximum MP of a character - Pastamancers and Saucerors specialize in Mysticality. A minimum amount of mysticality is also required to equip most accessories, and off-hand items (which can only be equipped with a weapon that is not 2-handed or more).
Moxie - determines the chance to evade an attack, or Agility in mainstream RPG's - Disco Bandits and Accordion Thieves specialize in Moxie. A minimum amount of moxie is also required to equip most ranged weapons, hats, and pants.
HP- "For those of you who have never played a computer game before, HP stands for Hit Points, or health in lesser circles. It's a measure of how much physical damage your character can take. When your Hit Points are reduced to zero, you cannot adventure until you regain some, either by using healing items or resting at your campsite. You also spend a few turns Beaten Up, which effectively reduces your primary statistics by half."
MP- "For Seal Clubbers and Turtle Tamers, MP stands for Muscularity Points. For Pastamancers and Saucerors, Mana Points. For Disco Bandits and Accordion Thieves, Mojo Points. MP is consumed when your character uses skills. MP can be regained via certain items, or by resting at your campsite. Your maximum MP is determined by your Mysticality experience." you must try it.

details from: http://en.wikipedia.org/wiki/Kingdom_of_loathing