A Student Visa is a type of visa that allows you to enter a foreign country and study at an educational institution. It's what you need to be able to enrol in a school or university in another country. Think of it as a permit to study abroad. Without it, you won't be able to attend class or live in the country. Now, different countries have different types of Student Visas, and they also have different requirements and fees. Therefore, it's important to research the specific details of the country you're planning to study in.