A visa is a permission stamp or sticker put into your passport that is issued by foreign embassies and consulates. A visa is often required so you can enter a foreign country. Many visas are stamps that are printed or stamped in your passport book. Most countries require visa stamps to enter for leisure or business travel. The requirements will vary and are based on your nationality, passport type, country of intended travel, and the reason for your travel. Travelers should ensure that their passport has at least six months of passport validity. Travelers should also make sure their passport has enough visa pages for the entry and exit stamps.