What's the use of passports, visas and exit certificates? What's the difference between them?

A "passport" is an identification document for going abroad to any region; The destination country allows passport holders to enter and stay; An "exit permit" is an identity document for traveling or trading abroad in a designated border area.

Passport is a valid international travel document issued by a country or region, which is used to prove the nationality and identity of a country's citizens or residents when they enter or leave the country or region and travel or stay abroad. Passport is a kind of passport for citizens to pass through international ports of various countries, and it is also an identity certificate for citizens to stay or transit abroad.

A visa is a document that a foreigner who travels is approved to enter the country of destination, which determines whether someone is allowed to leave the country. The visa stated that he was allowed to enter the country, the purpose of his entry and the duration of his stay. The purpose of the visitor's visit determines the time allowed to stay, from one day (such as transit) to permanent (such as immigration). Some visas are only allowed to be used once, such as transit and one-time travel. It is invalid if it is stamped with the entry and exit stamp. Others allow multiple uses, such as business, study, immigration (and many round-trip trips implemented in some countries recently) and so on. Any visa must indicate the time limit allowed to stay after entry.

Visa-free means that there is a bilateral agreement between two countries (such as China and Sri Lanka) that allows nationals of the other country to enter their own country without applying for a visa, which is called "mutual visa exemption". At this time, passengers from both countries can leave the country and enter the other country without visa inspection, and only need passports, valid air tickets and hotel reservation confirmation documents to be allowed to leave the country. This method is actually a special visa, which is a package visa for all nationals of another country according to the agreement, and it is not a "visa-free".

The exit permit, namely the Entry-Exit Pass, is an identity document for China citizens to engage in border trade, border tourism services or participate in border tourism on the border tourism routes approved by the competent department of the State Council or the State Council. I can apply for an exit permit from the exit-entry administration department of the public security organ of the local people's government at or above the county level in the border area, and enter and exit from the port designated by the Ministry of Public Security. For citizens engaged in border trade and border tourism services, valid entry and exit passes can be issued once a year or once every three months; Citizens who have been approved by the competent authorities of the State Council or the State Council to participate in border tourism may issue a valid entry and exit pass every three months.