I saved this for last because almost anything that can go in your inventory except gold pieces, horses, wagons, ships and potion ingredients, can show up as a magic item. Magic items could be weapons, armor, clothing, miscellaneous items or gems/semiprecious stones. The game will have some things show up as enchanted items that you cannot enchant. For example, holy daggers and holy tomes.  You can find out what these items do by either casting an "Identify" spell yourself or by having the item identified at any Mages Guild.  This service is available even if you are not a member of the Mages Guild.