A device designed to read information encoded into a small plastic card. It is often part of a data collection system in which each operator can be identified by the badge they present to the machine. It can also be used to control access to areas associated with electrically operated door locks, and when built into keyboards and other parts of information systems it can control access to information. The badge is usually of plastic, or paper laminated between plastic, and may contain a photograph and other information in addition to what is encoded. The encoding takes many forms, some of which are proprietary and complex to achieve greater security.