Pop 100

The Pop 100 was a weekly music chart launched by Billboard magazine in February 2005, designed to rank songs based on their mainstream pop appeal. Conceived by Michael Ellis, it combined airplay from Mainstream Top 40 radio stations with physical singles sales and digital downloads. Its introduction also coincided with the Hot 100 chart's significant change to include digital downloads, making the latter more comprehensive.

However, the Pop 100 was ultimately discontinued in June 2009 because the evolving Hot 100, with its greater emphasis on digital sales, became increasingly similar and effectively rendered the Pop 100 redundant. During its four-year run, the chart's first number one was "1, 2 Step" by Ciara featuring Missy Elliott in February 2005, and its final top spot went to "Boom Boom Pow" by The Black Eyed Peas in June 2009.