There are no purchasable items (but characters can be customized by learning talents as they level up). Experience is shared between all players on a team (so there is no benefit to last-hitting). However, it has a number of features which set it apart from other DOTA-style games.
Heroes of the Storm is a team-based competitive game in which each player controls a powerful hero with unique abilities, and works with his or her team to invade and destroy the enemy team's base.