depends on which systems you follow,but I think I'll just list the Warhammer lores.there's quite a list.
Lore of Death(not to be confused with necromancy)

OOM!!
Lore of Fire:self explanatory
Lore of Beasts:boost your own or a friendly units stats,prevent non-humanoid units from attacking
Lore of Light:to protect and heal
Lore of Metal:basically alchemy.improve your gear or make the enemys gear useless
Lore of Life:summon winds,or make the terrain itself strike out in anger!
Lore of the Heavens:thunderbolts,or unleash a comet on the battlefield
Lore of Shadow:speed around the battlefield,or scare the bejesus out of your foe
then there's the race-specific stuff.I won't go into detail.
Lore of the Old Ones (Lizardmen)
High Magic(High Elves)
Dark Magic(Dark Elves)
Lore of the Forest (Wood Elves)
Necromancy + Vampiric Magic
Lore of Chaos Undivided
Lore of Nurgle:disease and decay
Lore of Tzeentch:transformation and manipulation
Lore of Slaanesh

leasure and desire
Lore of the Horned Rat(Skaven[rat-men])
Gastromancy(Ogre's Gut Magic)
Big Waaagh! and little Waaagh! (orcs and goblins)
and the Lore of Ice,practised only by the Tzarina Katarina of Kislev.
I'm pretty sure I got them all.more information can be found at www.games-workshop.com