Overview#ICAO is an Abbreviation of International Civil Aviation Organization.
ICAO ICAO Document 9303 (endorsed by the International Organization for Standardization and the International Electrotechnical Commission as ISO/IEC 7501-1) and have a special Machine-Readable Zone (MRZ), which is usually at the bottom of the identity page at the beginning of a passport. The ICAO Document 9303 describes three types of documents. Usually passport booklets are issued in "Type 3" format, while identity cards and passport cards typically use the "Type 1" format. The machine-readable zone of a Type 3 travel document spans two lines, and each line is 44 characters long. The following information must be provided in the zone: name, passport number, nationality, date of birth, sex, and passport expiration date. There is room for optional, often country-dependent, supplementary information. The machine-readable zone of a Type 1 travel document spans three lines, and each line is 30 characters long.
Computers with a camera and suitable software 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.