Like Sgt. Pepper's Lonely Hearts Club Band is to a record collection, the Moody Blues are to popular music; a staple. Since their formation in 1964, the Moodies are often credited with developing and popularizing "orchestral rock." Their use of the Mellotron, a keyboard instrument, allowed them to replicate orchestral sounds both live and in the studio. Some of the Moodies' best-known songs include "Go Now," "The Story in Your Eyes," "Isn't Life Strange," "Question," "I'm Just a Singer (in a Rock 'n' Roll Band)" and the house favorite, "Nights in White Satin." The Moody Blues remain active touring and recording.