A record chart is a ranking of recorded music according to popularity during a given period of time. Examples of music charts are the Hit parade, Hot 100 or Top 40.

There are lots of different criteria used in different charts used to reflect popularity, commonly: sales of records, cassettes and compact discs; the amount of radio airplay; and (recently) the number of downloads.

Some charts are specific to a particular musical genre and most to a particular geographical location (although download charts are not easily pinned down in this way). The most common period of time covered by a chart is one week with the chart being printed or broadcast at the end of this time. Summary charts for years and decades are then calculated from their component weekly charts. Component charts have become an increasingly important way to measure the commercial success of individual songs.

A chart hit is an extremely popular recording, identified by its inclusion in a chart that uses sales or other criteria to rank popular releases. Chart-topper and related terms (like No. 1 hit, top of the charts, chart hit, and so forth) are widely used in common conversation and in marketing, and are loosely defined. In North America, the weekly charts from Billboard magazine are most often referenced (quite often internationally, as well), particularly the Billboard Hot 100 singles chart and Billboard 200 album chart, although there are many other charts and sources. Because of its value in promoting recording artists and releases, both directly to the consumer, and by encouraging exposure on radio, TV other media, chart positioning has long been a subject of scrutiny and controversy. Chart compilation methodology and data sources vary, ranging from buzz charts based on opinions of various experts and tastemakers, to charts that reflect empirical data such as retail sales. Therefore, a chart-topper may be anything from an "insiders' pick" to a runaway seller.

Robert Peter "Robbie" Williams (born 13 February 1974) is an English singer-songwriter, vocal coach and occasional actor. He is a member of the pop group Take That.

Williams rose to fame in the band's first run in the early- to mid-1990s. After many disagreements with the management and certain group members, Williams left the group in 1995 to launch his solo career. On 15 July 2010, it was announced he had rejoined Take That and that the group intended to release a new album in November 2010 which became the second fastest-selling album of all-time in UK chart history and the fastest-selling record of the century.

Williams has sold over 70 million records worldwide, which ranks him among the best-selling music artists worldwide. He is the best-selling British solo artist in the United Kingdom and the best selling non-Latino artist in Latin America. Six of his albums are among the top 100 biggest-selling albums in the United Kingdom. He has also been honoured with seventeen BRIT Awards—more than any other artist—and seven ECHO Awards. In 2004, he was inducted into the UK Music Hall of Fame after being voted as the "Greatest Artist of the 1990s."

Justin Drew Bieber ( /ˈbiːbər/ BEE-bər, born March 1, 1994) is a Canadian Pop/R&B singer-songwriter, musician, and actor. Bieber was discovered in 2008 by Scooter Braun, who came across Bieber's videos on YouTube and later became his manager. Braun arranged for him to meet with Usher in Atlanta, Georgia, and Bieber was soon signed to Raymond Braun Media Group (RBMG), a joint venture between Braun and Usher, and then to a recording contract with Island Records offered by L.A. Reid. Bieber's debut single, "One Time", was released in 2009 and peaked in the top twenty in Canada and charted in the top thirty in several international markets. His debut album, the seven-track EP My World, followed in November 2009, and was soon certified platinum in the United States. He became the first artist to have seven songs from a debut album chart on the Billboard Hot 100.