The Basic necessity of security can be attained by designing various door locks such as mechanical locks or electrical locks. These kind of door locks are designed with one or more keys, but for locking a large area various locks are needed.
Generally, traditional locks are heavy and that are not strong as they can damage simply by using some tools are better over mechanical locks, to resolve the security problems that are connected with the mechanical locks. In recent days every device uses digital technology. For example, identification of digital
device using token, door lock system using digital technology, automatic door opening and closing, automatic door lock systems, etc. These kind of systems is used for controlling the movement of a door without using a key.