A guard tour patrol system is a system for logging the rounds of employees in a variety of situations such as security guards patrolling property, technicians monitoring climate-controlled environments, and correctional officers checking prisoner living areas. It helps ensure that the employee makes his or her appointed rounds at the correct intervals and can offer a record for legal or insurance reasons. Such systems have existed for many years using mechanical watchclock-based systems (watchman clocks/guard tour clocks/patrol clocks). Computerized systems were first introduced in Europe in the early 1980s, and in North America in 1986. Modern systems are based on handheld data loggers and RFID sensors.