I will list a few of strong points and weak points for some units.

Camels and Heavy Camels: Strong vs about all other cavarlry, but weak to Infantry and archers

Knights,Cavalies, and Paladins: High attack,good for almost any battle, and good armour,good vs Archers and good for attacking siege weapons afar. Weak vs Mamelukes and Pikemen and Camels.

I will list more soon, but you can read about weakness and strong points in your guide book.