What are the key differences between a US visa B1 and B2, and how do they impact travel and stay in the United States?

A US visa B1 is for business purposes, while a B2 is for tourism or medical treatment. The key difference is the purpose of the visit. A B1 visa allows for business-related activities, such as meetings or conferences, while a B2 visa is for leisure or medical purposes. The type of visa impacts the activities allowed during the stay in the United States.