A travel document is an identity document issued by a government or international treaty organization to facilitate the movement of individuals or small groups of persons across international boundaries. Travel documents usually assure other governments that the bearer may return to the issuing country, and are often issued in booklet form to allow other governments to place visas as well as entry and exit stamps into them. The most common travel document is a passport, which usually gives the bearer more privileges like visa-free access to certain countries. However, the term is sometimes used only for those documents which do not bear proof of nationality, such as a refugee travel document.
In general, a passport is a travel document that also serves as proof of nationality from the issuing country. Although generally accepted by the majority of countries in the world, some issuing countries expressly exclude the validity of passports from nations that are not recognized by their governments.
Non-citizens in Latvia and Estonia are individuals, primarily of Russian or Ukrainian ethnicity, who are not citizens of Latvia or Estonia but whose families have resided in the area since the Soviet era, and thus have the right to a non-citizen passport issued by the Latvian government as well as other specific rights. Approximately two thirds of them are ethnic Russians, followed by ethnic Belarussians, ethnic Ukrainians, ethnic Poles and ethnic Lithuanians.
Non-citizens in the two countries are issued special non-citizen passports as opposed to regular passports issued by the Estonian and Latvian authorities to citizens. This form of legal discrimination is often labelled as xenophobic.
Although all U.S. citizens are also U.S. nationals, the reverse is not true. As specified in 8 U.S.C. § 1408, a person whose only connection to the U.S. is through birth in an outlying possession (which is defined in 8 U.S.C. § 1101 as American Samoa and Swains Island (which is administered as part of American Samoa)), or through descent from a person so born, acquires U.S. nationality but not U.S. citizenship. This was formerly the case in only four other current or former U.S. overseas possessions.