"Peg" is a song by rock group Steely Dan (formed by Donald Fagen and Walter Becker), which was released as a single from their 1977 album Aja.
The guitar solo on the track was attempted by seven top session guitarists before Jay Graydon's version became the "keeper". Rick Marotta played drums on the track; and the distinctive whistling sound in the intro is Tom Scott playing the lyricon, a type of electronic wind instrument.
The song describes a young female in a questionnable debut scene or photo shoot. She is warned that those images may "Come back to [her]". Note the playful reference to mid-20th century cinema and perhaps less-than-savory Times Square movie houses or magazines in the chorus: "you see it all," then quietly "in 3-D!"
The version on this post is a intrumental edit of "Peg", included in the record "Community Service" [CS-1].