Licensed datasets from Billboard, the Official Charts Company (UK), GfK Entertainment (Germany), and many other international reporting agencies that chart & rank the sales of top recorded popular music albums & singles from the 1950s to current. Also provides streaming audio links to copyright-cleared sound samples for most cited tracks & albums, and links to articles in popular music journals & on websites. Tools allow users to graph, analyze, compare, and contrast musical trends & interactions, and to extract & compare charting data for sound recording sales. Includes a module on the cultural impact of recorded music.