how is the episode structured?
It opens with a series of shots of New York City as the CBS Orchestra performed the "Late Show" theme, the night's guests are announced, as well as Paul Shaffer and the CBS Orchestra, then introduced Letterman.
Late Show with David Letterman
The show's opening credits featured a series of shots of New York City as the CBS Orchestra performed the "Late Show" theme (a livelier variation of the more jazzy "Late Night" theme). The announcer presented the names of that night's guests, as well as Paul Shaffer and the CBS Orchestra, then introduced Letterman. 
what is just a girl? A song by American band No Doubt who created it? Gwen Stefani and Tom Dumont who was the vocalist of the song? Gwen Stefani has it been performed live anywhere? Yes - Virgin Megastore in Los Angeles, on the American TV show "Late Night with Conan O'Brien" , Late Show with David Letterman" what kind of show is the last one? An American late-night talk show hosted by David Letterman what are some of the notable episodes? Appearances by Regis Philbin, Marv Albert, Jack Hanna
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Late Show with David Letterman [SEP] Episode structure
The show's opening credits featured a series of shots of New York City as the CBS Orchestra performed the "Late Show" theme (a livelier variation of the more jazzy "Late Night" theme). The announcer presented the names of that night's guests, as well as Paul Shaffer and the CBS Orchestra, then introduced Letterman. On rare episodes, the show began with a cold open as Letterman, dressed casually, briefly interacted with a celebrity or performed a short sketch backstage before the traditional opening sequence began. In the last few years, Alan Kalter included himself in the introduction. In addition, Letterman took to dashing across the stage either just before, while, or just after Kalter introduced him.