Nielsen SoundScan is an information and sales tracking system created by Mike Fine and Mike Shalett. Soundscan is the official method of tracking sales of music and music video products throughout the United States and Canada. Data is collected weekly and made available every Wednesday to subscribers, which include executives from all facets of record companies, publishing firms, music retailers, independent promoters, film and TV, and artist management. SoundScan is the sales source for the Billboard music charts, making it the official source of sales records in the music industry.

Nielsen SoundScan began tracking sales data for Nielsen since March 1, 1991. The May 25 issue of Billboard published Billboard 200 and Country Album charts based on SoundScan "piece count data," and the first Hot 100 chart to debut with the system was released on November 30, 1991. Previously, Billboard tracked sales by calling stores across the U.S. and asking about sales - a method that was inherently error-prone and open to outright fraud.^{[citation needed]}

Keith L. Clark is a Professor of Computer Science at Imperial College London, England. He has lectured in both mathematics and computer science. Since 1979 he has had a tenured position in the Department of Computing, Imperial College London, where he has been Professor of Computational Logic since 1987. Between 1987 and 1995 he was also Visiting Professor at Uppsala University. He is currently a Visiting Professor at BTH (since 1997), and at the University of Queensland (since 1998). In 1980 he co-founded an Imperial College spin-off company, Logic Programming Associates, to develop and market Prolog systems for micro-computers (micro-Prolog) and to provide consultancy on expert systems and rule based applications.

His key contributions have been in the field of logic programming. His 1978 paper on negation as failure was arguably the first formalisation of a non-monotonic logic. His 1981 paper on a relational language for parallel programming introduced concurrent logic programming.

Recently he has been working on the April and Go! programming languages and their application to agent programming.

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.