Necromagic

Necromagic is a professional term for necromancy. It allows the caster to resurrect creatures into his temporary servants. It is not a 'true' Undeath Magic, nor the 'truest' Heresy Magic. It works by pure thaumaturgy, using magic power to reanimate dead bodies and give them some semblances of consciousness.
It also includes - by association - thaumaturgic hexes that allow to manipulate dead bodies in a directly offensive or defensive ways (like using bones of the fallen as projectiles or detonating dead boedies). It is, however, mostly secondary in importance to standard Death Magic.

Subschools of the Necromagic

Bone Magic [HX] - Magic that allows one to either animate skeletons of a variety of creatures to use them as a cannonfodder (or simply combatants, sometimes of great strength) creatures, or manipulate/conjure bones to use as a shields, projectiles etc.
It has little to do in terms of the offensive, but the things it reanimates are pretty decent as defenders.
Corpse Magic [HX] - Magic that allows the caster to reanime the creature as his defender in its corporal form. Unlike creatures made from Bone Magic, the resurrected creatures possess some remnants of their former skills. On the other hand, unlike things resurrected with the Undeath Magic, they are subjected to entropy and rot, quite quickly losing said skills.
It can also be used to detonate bodies and do few similar tricks with corporal bodies.
Spirit Magic [HX] - Magic that allows to summon spiritual remnants of the dead creatures. While they lack their corporal bodies, they retain a lot of their pre-death intellect and can use magic. Plus, they are incorporeal, which is often very useful upon the battlefield. There are also some hexes that use said spiritual remnants in a more directly offensive ways.
Contrary to some superstitions, the Spirit Magic has nothing to do with souls. The remnants it summon are leftovers after one's soul departed into the Afterlife. It is completely safe to do, but still treated with distrust by many.
Soul Magic [HX][E][P] - A very distrusted school of magic that deals with the souls of the living beings. The difference between Soul Magic and Heresy Magic is that Sould Magic sticks to the parts of soul manipulation that Gods permit. Main part of it are hexes that can temporarily sever or weaken the connection between soul and body - causing a variety of powerful debuffs. There are also hexes that can create fake, artificial souls then used to possess various things (like animals, items etc.).
The Soul Magic was split into two parts following the Dawn War, when Malice usurped control over the Heresy Magic.