When talking travel and talking visas, they aren't referring to credit cards! A visa is the stamp in your passport that tells you how long you are able to stay in that country for.  Every country requires a visa to enter their country, and sometimes you can just arrive in that country and they'll stamp your passport on arrival, and other times you'll need to apply for your visa ahead of time.  If you are ever curious about whether or not you'll need a visa, please contact us and we'll let you know!