There are thousands of items to collect throughout the Order & Chaos world that all serve have different purposes. Items are all the things that you can add to your bag (inventory).
Generally they can be broken up into four categories.
Consumable’s Page
Just as the name states consumables are items that a player can consume. These include the obvious like potions and food (that fill your health and mana bar over time) and not so obvious things like items that buff your stats for a period of time.
Materials
Used in crafting to create armor and weapons (so far). They can be anything from armor scraps, to minerals.
Equipment – This is everything that a player can where (or equip..see what they did there?). This includes all armor, weapons, trinkets, rings, etc.
Misc – These are the junk items that are made only to sell to vendors for money. They are grey in color so you know they aren’t used for anything. This is how they can justify crocodiles not wandering around with gold on their corpses…Also encourages a player to buy more storage in their bag, which makes Gameloft more bucks. 
Vanity Pets would also fall into this category as they cause no direct benefits to the player beyond being a cute companion.