I assume that you are talking about internet piracy, not the sort that is going on in Somalia.
This sort of piracy affects different people in different ways. For regular consumers, piracy affects them by saving them money and/or by giving them access to things they would not otherwise have had. For example, a consumer who would not have paid to buy the latest Harry Potter movie might get it via piracy.
On the other side of the equation, piracy hurts producers. It means that the firms that produce the movies get less money. It also hurts "little people." It may hurt people who work at theaters because fewer people attend movies. It might hurt people who work for firms like Netflix because fewer people will pay to stream the movies legally.