A Canadian visa is an official document issued by the Government of Canada that allows foreign nationals to enter and stay in Canada for a temporary or permanent period of time. There are various types of Canadian visas, including tourist visas, student visas, work visas, and permanent resident visas. The type of visa required depends on the purpose of the individual's visit, their country of citizenship, and their length of stay in Canada. The process of obtaining a Canadian visa involves submitting an application, providing documentation and meeting the eligibility criteria set out by the Canadian government.