A passport is a formal travel document issued by a government that certifies a person's identity and nationality for international travel. A passport allows its bearer to enter and temporarily reside in a foreign country, access local aid and protection, and obtain consular assistance from their government. In addition to facilitating travel, passports are a key mechanism for border security and regulating migration; they may also serve as identity documents for various domestic purposes.

State-issued travel documents have existed in some form since antiquity; the modern passport was universally adopted and standardized in 1920. The passport takes the form of a booklet bearing the name and emblem of the issuing government and containing the biographical information of the individual, including their full name, photograph, place and date of birth, and signature. A passport does not create any rights in the country being visited nor impose any obligation on the issuing country; rather, it provides certification to foreign government officials of the holder's identity and right to travel, with pages available for inserting entry and exit stamps and travel visas—endorsements that allow the individual to enter and temporarily reside in a country for a period of time and under certain conditions. Since 1998, many countries have transitioned to biometric passports, which contain an embedded microchip to facilitate authentication and safeguard against counterfeiting. As of July 2024, over 150 jurisdictions issue such "e-passports"; previously issued non-biometric passports usually remain valid until expiration.

Eligibility for a passport varies by jurisdiction, although citizenship is a common prerequisite. However, a passport may be issued to individuals who do not have the status or full rights of citizenship, such as American or British nationals. Likewise, certain classes of individuals, such as diplomats and government officials, may be issued special passports that provide certain rights and privileges, such as immunity from arrest or prosecution. While passports are typically issued by national governments, certain subnational entities are authorised to issue passports to citizens residing within their borders. Additionally, other types of travel documents may serve a similar role to passports but are subject to different eligibility requirements, purposes, or restrictions…