What does a yellow buoy mark in the ocean?

A yellow buoy in the ocean typically marks a safe navigation route or indicates a caution area, such as a channel for vessels or a regulated zone for activities like fishing or swimming. It can also signify the presence of underwater hazards or specific marine areas, such as those for marine wildlife protection. The exact meaning can vary based on local regulations and maritime practices. Always refer to navigational charts for specific meanings in a given area.