After setting up the formation (which will be discussed in another part of the tutorial in detail), your generals will lead your army to battle.
There are five troop categories in the game:
Infantry (I)
Cavalry (C)
Archers (A)
Mages (M)
Support (S)

Each of these troop categories is then further sub-divided into troop types.

For example, in the Infantry category, we have:
Heavy Spearguard, which have high defense
Maulers, which deals heavy damage to enemies in a column
Berserkers, which deals heavy damage to a single target
Marauders, which attacks the enemy from behind
Troop types, along with the specific ability of a general, make every general unique in this game.