Flightradar24 is an internet-based service that shows real-time aircraft flight information on a map. It includes flight tracks, origins and destinations, flight numbers, aircraft types, positions, altitudes, headings, and speeds. Flightradar24 can also show time-lapse replays of previous tracks and historical flight data by airline, aircraft, aircraft type, area, or airport. It aggregates data from multiple sources but, outside of the USA, mostly from crowdsourced information gathering by volunteers with ADS-B receivers.