Nielsen Broadcast Data Systems, better known as BDS, is a service that tracks monitored radio, television and internet airplay of songs based on the number of spins and detections. The service, which is a subsidiary of ACNielsen provides the basis for Nielsen Media publication Billboard in the United States, while in Canada, BDS helps determine the Canadian BDS Airplay Chart and the Canadian Hot 100 chart, which is published by Jam! and in the website for Canadian Music Network, in determining their radio airplay music charts and determines the chart movement in Billboard's Hot 100 chart when combined with single sales from Nielsen SoundScan. From August 2006 to its final June 2009 publication, BDS also provided chart data for R&R after Nielsen acquired the trade. On September 10, 2009, the website Radio-Info.com struck a partnership with Nielsen BDS to provide radio airplay charts and related data for over 20 formats.
Using a patented digital pattern recognition technology, Nielsen BDS captures in excess of 100 million song detections annually on more than 1,600 radio stations in over 140 U.S. markets (including Puerto Rico), 30 Canadian markets and the 3 major markets in Mexico. Nielsen BDS also uses the service to track monitored airplay at satellite radio (Sirius XM), internet services (like Yahoo! and AOL) and audio networks (like Dial Global, Music Choice and Radio Disney), as well as on TV (12 U.S. music video channels and 9 Canadian video channels).
Since its 1992 debut, BDS has become the standard for the radio and music industry because of its accuracy of detecting, tracking and monitoring songs, thus eliminating the use of reporting and call-outs to trades and record labels when it comes to adding and testing tracks. The method has also helped tracks that only received airplay (songs that are not released as singles) become major hits, especially in Billboard's Hot 100 chart, where several radio-only tracks have reached the top spot.