Mark Snow (born Martin Fulterman; August 26, 1946) is an American composer for film and television. Among his most famous compositions is the theme music for the science fiction television series The X-Files. 

The X Files instrumental was released as a single in the United Kingdom, where the series aired on BBC Two and BBC One in early 1996, peaking at number two on the UK Singles Chart. Snow also wrote the music for another Chris Carter series, Millennium, and the background music scores for both shows, a total of 12 seasons. Snow composed scores for notable television, including Hart to Hart, Starsky & Hutch (season 3), and Smallville.

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