What's the difference between a visa page and a passport?

There are two situations in which there is a visa on the passport visa page:

1. sticker visa

Sticker visa is widely used in most countries in the world. As the name implies, a visa is attached to your passport and must be presented at the same time to be valid.

2. Separate visa

Visa will be issued separately for all countries, and passports will not be changed. You must use a separate visa at the same time as your passport to effectively achieve the purpose of entry and exit. Generally, a photo of the applicant is attached to a separate visa, and the contents exactly the same as those in the applicant's passport and the precautions for simultaneous use are stated.