The availability of high-quality DRM-free tracks contributed to a 188 percent growth in music sales at UK online retailer 7digital last year, the company claims.

The company also revealed its top-selling albums of 2007, including five albums from Radiohead, which aren't available through iTunes because Apple won't allow the band to license the tracks as an entire collection. Top selling albums include Kylie, Arctic Monkeys and The White Stripes.

The removal of DRM and availability of high-quality 320Kbps format MP3 tracks has resulted in massive surge in the popularity of digital music and year-on-year sales growth of 188 percent, the company said.

"The 2007 charts reveal the increasingly popularity of digital music," said Ben Drury, MD of 7digital. "Alongside some of the year's big album releases, such as Kylie and Arctic Monkeys, we also find five back catalogue Radiohead albums that were only released in digital format late in the year."

He continued: "2008 is set to be the year DRM is gone for good. We've already seen all four majors make efforts to offer DRM-free downloads and by the summer DRM will likely be resigned to the history books."

7digital expects to abandon DRM across all of its song catalogue by the end of 2008, selling tracks in DRM-free MP3 format means songs sold by the company will be compatible with iPods, iPhones and many other players and platforms.