Items are a special type of Artifact cards that are purchased for Gold. Gold is acquired by killing heroes or creeps. Items are purchased from a second deck of nine cards that you build beforehand, called Secret Shop. Each hero has three item slots: Weapon, Armor and Accessory . New items will override old ones  and they will stay on the hero even on death. Additionally, there are consumable items, which provide one-time effects, e.g healing a hero.
List of Items
(Items are sorted by gold cost)