"Jessica" is a rock instrumental written by Dickey Betts, guitarist of The Allman Brothers Band, and Les Dudek, who played with them soon after Duane Allman's death.[1]

Jessica was first released on the band's 1973 album Brothers and Sisters, and has subsequently been used in many musical contexts. In January 2006, a Wall Street Journal article referred to the piece as "a true national heirloom." It is widely known as the theme to the BBC Two motoring programme Top Gear and its popular reformatted revival.

The piece, along with "Ramblin' Man", is one of the two tracks from the album which marked the beginning of a new era for the Allman Brothers Band following the deaths of Duane Allman and Berry Oakley. The song is named for Jessica Betts, the daughter of Dickey Betts and Sandy Bluesky.
from the album Brothers and Sisters

Released  August 1973
Recorded  1972
Genre  Southern rock, instrumental rock
Length  7:28
Label  Capricorn Records
Writer(s)  Dickey Betts and Les Dudek
Producer  Johnny Sandlin, The Allman…

The theme song for Top Gear

The song is originally called Jessica by the Allman Brothers Band.

Top Gear is a BBC television series about motor vehicles, primarily cars. It began in 1977 as a conventional motoring magazine show. Over time, and especially since a relaunch in 2002, it has developed a quirky, humorous style. The show is currently presented by Jeremy Clarkson, Richard Hammond and James May, and also features a test driver known as The Stig. The programme is estimated to have 350 million viewers worldwide.

External Links:
United Kingdom: http://www.topgear.com/uk/
United Kingdom: http://www.topgear.com/uk/tv-show
United States: http://www.bbcamerica.com/shows/topgear/
Australia: http://www.topgear.com/au/