What is Red lighted buoy with the number 6?

A red lighted buoy with the number 6 is a navigational aid used in marine environments to mark specific locations or hazards in waterways. The red color indicates that it is a port or left-hand marker when approaching from seaward, following the IALA buoyage system. The number 6 helps mariners identify their position relative to charts and other navigational information. The light on the buoy aids visibility during nighttime or poor weather conditions.