The Billboard charts tabulate the relative weekly popularity of songs or albums in the United States. The results are published in Billboard magazine. The two primary charts – the Hot 100 (top 100 singles) and the Billboard 200 (top 200 albums) – factor in airplay, as well as music sales in all relevant formats.

On January 4, 1936, Billboard magazine published its first music hit parade. The first Music Popularity Chart was calculated in July 1940. A variety of song charts followed, which were eventually consolidated into the Hot 100 by mid-1958. The Hot 100 currently combines single sales, radio airplay and digital downloads.

All of Billboard's charts use this basic formula. What separates the charts is which stations and stores are used – each musical genre having a core audience or retail group. Each genre's department at Billboard is headed up by a chart manager, who makes these determinations.

For many years, a song had to be commercially available as a single to be considered for any of Billboard's charts. At the time, instead of using SoundScan or BDS, Billboard obtained its data from manual reports filled out by radio stations and stores. According to the 50th Anniversary issue of Billboard, prior to the official implementation of Nielsen SoundScan tracking in November 1991, many radio stations and retail stores removed songs from their manual reports after the associated record labels stopped promoting a particular single. Thus songs fell quickly after peaking and had shorter chart lives. In 1990, the country singles chart was the first chart to use SoundScan and BDS. They were followed by the Hot 100 and the R&B chart in 1991. Today, all of Billboard's charts use this technology.

Michael Joseph Jackson (August 29, 1958 – June 25, 2009) was an American recording artist, entertainer, and businessman. Often referred to as the King of Pop, or by his initials MJ, Jackson is recognized as the most successful entertainer of all time by Guinness World Records. His contribution to music, dance, and fashion, along with a much-publicized personal life, made him a global figure in popular culture for over four decades. The seventh child of the Jackson family, he debuted on the professional music scene along with his brothers as a member of The Jackson 5 in 1964, and began his solo career in 1971.

In the early 1980s, Jackson became a dominant figure in popular music. The music videos for his songs, including those of "Beat It", "Billie Jean", and "Thriller", were credited with transforming the medium into an art form and a promotional tool, and the popularity of these videos helped to bring the relatively new television channel MTV to fame. Videos such as "Black or White" and "Scream" made him a staple on MTV in the 1990s. Through stage performances and music videos, Jackson popularized a number of complicated dance techniques, such as the robot and the moonwalk, to which he gave the name. His distinctive musical sound and vocal style influenced numerous hip hop, post-disco, contemporary R&B, pop and rock artists.

Taylor Alison Swift (born December 13, 1989) is an American singer-songwriter and occasional actress. Raised in Wyomissing, Pennsylvania, Swift moved to Nashville, Tennessee at the age of fourteen to pursue a career in country music. She signed to the independent label Big Machine Records and became the youngest songwriter ever hired by the Sony/ATV Music publishing house. The release of Swift's self-titled debut album in 2006 established her as a country music star. "Our Song", her third single, made her the youngest sole writer and singer of a number one song on the country chart. She received a Best New Artist nomination at the 50th Grammy Awards.

Swift's second album, Fearless, was released in late 2008. Buoyed by the chart success of the singles "Love Story" and "You Belong with Me", Fearless attracted a crossover audience and became the top-selling album of 2009. The record won four Grammy Awards, with Swift becoming the youngest ever Album of the Year winner. Fearless also received Album of the Year plaudits at the American Music Awards, Academy of Country Music Awards and Country Music Association Awards, making it the most awarded album in country music history. In 2010, Swift released her third album, Speak Now, which sold over one million copies in its first week. She then embarked on the 111-date Speak Now World Tour, which was attended by over 1.6 million fans and has become one of the highest-grossing concert tours of all time. The album's third single, "Mean", won two Grammy Awards for Best Country Song and Best Country Solo Performance. Swift is currently recording her fourth studio album, due for release in the fall of 2012.