In some form or another, access control is present in our lives on a daily basis, for example, a lock on the door or a PIN code for the ATM. Formally, access control systems are designed to allow control over access to specific areas and resources. The use of access control is of importance when seeking to protect important, confidential, or sensitive information or equipment.

Physical access control is a matter of who, where, when as an access control system determines who is allowed to enter or exit, where they are allowed to enter or exit, and when they are allowed to enter or exit.