Keycard lock

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

[citation needed] Mechanical keycard locks employ detainers which must be arranged in pre-selected positions by the key before the bolt will move.

RFID cards contain a small chip and induction loop which the transmitter on the keycard reader can access.

The main advantages with RFID cards is that they do not need to be removed from the wallet or pass holder - as the keycard reader can usually read them from a few inches away.

Computerized authentication systems, such as key cards, raise privacy concerns, since they enable computer surveillance of each entry.

Many modern households have installed digital locks that make use of key cards, in combination with biometric fingerprint and keypad PIN options.