Billboard has introduced new digital download lists ranking the top songs in 21 specific genres, compiled from data gathered by Nielsen SoundScan.

Each week in the magazine Billboard will include six 15-position digests of digital genre song charts, with rock, country, R&B/hip-hop and Latin running each week and two other genres rotating. All charts appear at their full depths on billboard.biz, where Billboard's entire menu of charts is refreshed each Thursday.

As with Billboard's album rankings, the charts department reviews hundreds of song titles per week, assigning an appropriate genre or genres, or confirming a label's requested classification, to each entry.

"Billboard is always thrilled to launch songs charts that reflect evolving consumer purchasing tastes," says Billboard director of charts Silvio Pietroluongo. The digital genre rankings are a great way to drill down beyond the overall top-selling download titles to see which songs and artists are the hottest in a multitude of specific genres."