Burnham v. Superior Court is a significant Supreme Court case from 1990 that addressed the issue of personal jurisdiction in relation to a non-resident defendant physically present in a state. The ruling established that a state could exercise personal jurisdiction over an individual based on their physical presence in the state, reinforcing the concept of 'tag jurisdiction.' This case is important for understanding how in-person contacts with a state can establish jurisdiction, particularly in the context of in rem and quasi in rem jurisdiction.