Automatic number plate recognition (ANPR; see also other names below) is a mass surveillance

Mass surveillance

Mass surveillance is the pervasive surveillance of an entire population, or a substantial fraction thereof.Modern governments today commonly perform mass surveillance of their citizens, explaining that they believe that it is necessary to protect them from dangerous groups such as terrorists,...

 method that uses optical character recognition

Optical character recognition

Optical character recognition, usually abbreviated to OCR, is the mechanical or electronic translation of scanned images of handwritten, typewritten or printed text into machine-encoded text. It is widely used to convert books and documents into electronic files, to computerize a record-keeping...

 on images to read the license plates on vehicles. They can use existing closed-circuit television

Closed-circuit television

Closed-circuit television is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors....

 or road-rule enforcement camera

Road-rule enforcement camera

A traffic enforcement camera is an automated ticketing machine...

s, or ones specifically designed for the task. They are used by various police forces and as a method of electronic toll collection

Electronic toll collection

Electronic toll collection , an adaptation of military "identification friend or foe" technology, aims to eliminate the delay on toll roads by collecting tolls electronically. It is thus a technological implementation of a road pricing concept...

 on pay-per-use roads

Road pricing

Road pricing is an economic concept regarding the various direct charges applied for the use of roads. The road charges includes fuel taxes, licence fees, parking taxes, tolls, and congestion charges, including those which may vary by time of day, by the specific road, or by the specific vehicle...

 and cataloging the movements of traffic or individuals.

ANPR can be used to store the images captured by the cameras as well as the text from the license plate, with some configurable to store a photograph of the driver.