Keycard lock

A keycard lock is a lock operated by a keycard, a flat, rectangular plastic card with identical dimensions to that of a credit card or American and EU driver's license which stores a physical or digital signature which the door mechanism accepts before disengaging the lock.

There are several common types of keycards in use, including the mechanical holecard, barcode, magnetic stripe, Wiegand wire embedded cards, smart card (embedded with a read/write electronic microchip), and RFID proximity cards.

Keycards are frequently used in hotels as an alternative to mechanical keys.

The first commercial use of key cards was at automated parking lots to raise and lower the gate where users paid a monthly fee.

Overview

Keycard systems operate by physically moving detainers in the locking mechanism with the insertion of the card, by shining LEDs through a pattern of holes in the card and detecting the result, by swiping or inserting a mag stripe card, or in the case of RFID cards, merely being brought into close proximity to a sensor. Keycards may also serve as ID cards.