Time and attendance and access control are the most commonly used identification systems that are mediated by different types of ID cards (RFID, bar code, smart, etc..) And the corresponding reader, fingerprint recognition or human figure.
For time is usually interact with RFID cards (contactless) that employees receive and at each pass through the gate "squeeze" your card near the reader, which registers the input, output, or some of the particular options given (officially or personal outings, etc.).
Readers are connected to a central database on a server which records the time and purpose of each entry and exit, and therefore can receive reports on the working hours of employees that can be used in programs for the calculation of personal income.
Next to each reader it is desirable to install the camera, with which the server gets a picture of each person who has entered or exited the circle of companies.
Except for time, a very broad application of the records of clients, ie. customers, collection of parking, registration poured fuel pumps, electronic payment, or any other form of records of persons, goods and so on.
In addition to time and attendance, there is also an option for access control that allows you to specify where anything goes and where can one enter into certain rooms or other facilities. For the commonly used electrical or electro-magnetic locks that running an organization comes RFID readers.