Enter the code!
The Arduino could be used to do many security or automated tasks they could be used to log events, keep track of doors and entry code to doors even monitor temperatures and detect movement. The fact is that this low cost device has only the limits of the imagination.
You can now have your own biometrics integrated into your products so facial recognition, finger print scanning can be used for security, logging and so much more and with other forms of AI using Micro controllers is a low cost and effective way to fund your projects, this is also useful for hobbyists - example my mother in law and family sometimes forget to bring the door keys, a finger print ID would be helpful them gain easy access back in to the house, this could also contain a keycode pad too for second level option.
The Arduino is used in many industries now and is a low cost and low power device which can handle almost any task you require people are using these as:-
Webcam and Smart Security Cameras
Car Alarms & GPS Tracking
Mobile Phones & GSM devices
House Alarms & Security