Buoy. A buoy is a floating device that can have many purposes.
It can be anchored or allowed to drift with ocean currents. Race course marker buoys are used for buoy racing, the most prevalent form of yacht racing and power boat racing.
They delimit the course and must be passed to a specified side. They are also used in underwater orienteering competitions.
Emergency wreck buoys provide a clear and unambiguous means of temporarily marking new wrecks, typically for the first 24-72 hours. They are coloured in an equal number of blue and yellow vertical stripes and fitted with an alternating blue and yellow flashing light.
They were implemented following collisions in the Dover Strait in 2002 when vessels struck the new wreck of the MV Tricolor. Ice marking buoys mark holes in frozen lakes and rivers so snowmobiles do not drive over the holes. Large Navigational Buoys are automatic buoys over 10 m high equipped with a powerful light monitored electronically as a replacement for a lightvessel. They may be marked on charts as a Superbuoy. Lateral marker buoys. Safe water mark or fairway buoys mark the entrance to a channel or nearby landfall. Sea marks aid pilotage by marking a maritime channel, hazard or administrative area to allow boats and ships to navigate safely. Some are fitted with wave-activated bells or gongs. Wreck buoys mark a wrecked ship to warn other ships to keep away bec