ICAO Document 9303 describes three types of Machine Readable Travel Documents. Specifications for the Security of the Design, Manufacture and Issuance of MRTDs
The following information must be provided in the zone:
devices can directly read the information on Machine Readable Passports. This enables faster processing of arriving passengers by immigration officials, and greater accuracy than manually read passports, as well as faster data entry, more data to be read and better data matching against immigration databases and watchlists.
Apart from optically readable information, many passports contain an RFID chip which enables computers to read a higher amount of information, for example a photo of the bearer. These passports are called Biometric Passports.