A door closer is a device that closes a door in a controlled manner, generally preventing it from slamming after someone opens it or after it is automatically opened. Thus, it minimizes the vulnerability of the door to remain open while separating the space. In addition, the door and door hardware are protected as they are not exposed to hard impacts; a comfortable opening and closing is provided. The force used to open the door is stored in a kind of spring and when released, this energy is used to return the door to the closed position. Door closers can also be connected to a building's fire alarm system.