Access control system (ACS) is a type of security that manages and controls who or what is permitted to enter a system, environment, or facility. In the area of physical security and information security, access control (AC) is the selective check of access to a place or other resource. Permission to access a resource is called authorization.
The purpose of an access control system is to give quick, convenient access to those persons who are authorized, while, restricting access to unauthorized people. Electronic access control uses computers to solve the drawback of mechanical locks and keys.