"It's a Good Day" is a popular song written by Peggy Lee and Dave Barbour and published in 1947.
The song has been recorded by many singers since its introduction, most recently by Susie Arioli. The song was also recorded by legendary Judy Garland on a recording of The Judy Garland Show. The most popular version of the song is probably Perry Como's, released on his 1955 RCA Victor album So Smooth.
The song served as the background score during the opening credits of Indian film director Rajkumar Gupta's 2008 debut film Aamir.