An ePassport (biometric passport) is a combined paper and electronic identity document that uses biometrics to authenticate the citizenship of travelers. The passport's critical information is stored on a tiny RFID computer chip, much like information stored on smartcards. Like some smartcards, the ePassport book design calls for an embedded contactless chip that is able to hold digital signature data to ensure the integrity of the passport and the biometric data.

Privacy activists in many countries question and protest the lack of information about exactly what the passports' chip   may contain, and whether they impact civil liberties. The main problem they point out is that data on the passports can be transferred with touchless RFID technology (like wireless technology) which can become a major vulnerability. Although this would allow ID-check computers to obtain your information without a physical connection, it may also allow anyone with the necessary equipment to perform the same task. If the personal information and passport numbers on the chip aren't encrypted, the information might wind up in the wrong hands.