The melee adventure schools are the close combat schools that use hand to hand combat.
A beserker trades off more two-handed damage per second versus weaker armor. You could argue that the lesser armor allows a beserker to inflict greater damage as it allows a more flexibility and thus deflect more attacks. Beserkers gain max evasion and max strength per level. Beserker is an advanced school that can be joined once players have reached level 20 as a Warrior.
A Cleric is a fighter but also a healer. A Cleric can wear the best armor (platemail) and also has skills in Life which allows them to heal themselves or others during combat.Although not the highest at damage output, a Cleric is skilled with use of a shield and as such can block incoming attacks. An added bonus is the ability to cast augmentation spells which can bestow themselves or group members with gifts and enhances during combat.
Monks are the hard core lement in Istaria. They trade off armor and weapons for hand to hand fighting and increased dexterity and evasion. As such a monk receives max dexterity and evasion when compared to other schools. Not an easy school to level, however at high level they come into their own.
Paladins are an extension of Warrior and Cleric. Able to wear the best armor in game (Platemail) the are geared for damage against undead foes. They receive max one hand slash and two hand slash skills and are proficient with the use of a shield. Additionally they recieve Life and Augmentation skills (although not as much as a Cleric or Healer) which allows them to provide limited heals and buffs enhances to other members of a group. Paladin is borderline being a true melee school or a combo school (due to skills in Life).
A Spearman is a warrior that has chosen to specialise in the use of piercing and a combination of using a shield. As such they gain the best one hand piercing skills when compared to the other schools. Blocking and deflecting attacks are also part of s spearmans arsenal.
The all-rounder for melee. Being a warrior opens up a myriad of advanced schools where a player can refine their skills. A warrior is skilled in the use of slashing, piercing and crushing weapons with or without a shield. To note level 20 as a warrior normally opens up access to the advanced schools.