Flightradar24 is a flight tracking service that provides real-time aircraft flight information on a map. Here's a summary with potential YouTube keywords:

• Flight Tracking: Flightradar24 provides live tracking of aircraft using data from various sources.
• ADS-B: The primary data source is ADS-B transponders on aircraft, which transmit positional data to a network of ground-based receivers. Flightradar24 has a network of over 40,000 connected receivers.
• MLAT: Multilateration (MLAT) is used to track aircraft without ADS-B transponders, requiring at least four receivers to calculate an aircraft's position.
• Satellite Data: Satellite-based ADS-B data is used for aircraft outside of the terrestrial network coverage area.
• Real-time Flight Map: The service displays aircraft moving on a detailed map. Users can view flight details by tapping on an aircraft, including route, estimated time of arrival, aircraft type, speed, and altitude.
• Historical Flight Data: Users can view historical data and watch playbacks of past flights.
• App Features: Flightradar24 offers mobile apps for iOS and Android devices. These apps allow users to identify flights overhead by pointing their device at the sky. They also offer 3D views, search functionality, filters, and more.
• Subscription Options: While the basic app is free, there are Silver and Gold subscription options that provide access to additional features, such as more flight history, weather overlays, and aeronautical charts.
• Crowdsourced Data: The service relies heavily on crowdsourced data from volunteers who operate ADS-B receivers.
• Global Coverage: While most of the data is from crowdsourced ADS-B receivers, coverage is also supplemented by radar data, especially in the US, Canada, and Australia.
• Entertainment Purposes: The apps are intended for entertainment and not for any activity that could endanger lives.

Potential keywords: flight tracker, live flight tracking, ADS-B, MLAT, real-time flight map, aircraft tracking app, plane spotting, aviation, flight radar, Flightradar24, ADS-B receiver, aircraft data, flight path.