If we visit a country, then, the main requirement besides having to have a passport we must also have a visa document, then what is Visa? And what is the Visa function?
A visa is a person’s admission document to a country that can be obtained at an embassy where the country has a consulate general or a foreign embassy. Then, we need to fulfill all the requirements for the passport designed by each of the government whose country we wish to visit. For example, if you want to visit England as an immigrant, then, you need to take a B1 test as one of the requirements. You can take the test on http://britishlifeskills.com.
A visa is a proof to allow to visit a place if it enters a territory of another country requiring entry permission. Visa documents can take the form of visa stickers that can be viewed at the embassy of the country to be visited or stamped on a passport in a particular country.