There will be five different crafting professions in the Elder Scrolls Online. They are provisioner, enchanter, weaponsmith, armorsmith and alchemist. Through each of these profession you will be able to craft special items that you will not find anywhere else in the game.
The provisioner is basically a cook. You can take food items that you will find on quests and cook them to create better food. For example, if you find meat, you can cook the meat over any fire you come across. There will be recipes that will call for certain ingredients that will allow the player to make things like stew or pie.
The weaponsmith and armorsmith will be able to create armor and weapons of different eso races such as orcish armor. Each race will have the ability to create their default armor at the beginning of the game but, will have to discover the recipes for all other types of armor before it can be created. Armor and weapons will be created at an anvil or forge.
Enchanters are able to take already made weapons and armor and add abilities to them like for instance if you have a pair of boots on you and want them to hold a special power like life regeneration, an enchanter can do that at an enchantment table.
The alchemist will be able to use certain ingredients, depending on the recipe to make potions. These potions will all have different effects depending on which recipe was used. The potions will of course be created at an alchemy laboratory.