Happy Days (TV theme) performer Pratt & McClain
"Happy Days" is a song written by Norman Gimbel and Charles Fox. It is the theme of the 1970s television series Happy Days.  It can be heard during the TV show's opening and closing credits as it runs in perpetual rerun syndication.
"Happy Days" was first recorded in 1974 by Jim Haas with a group of other session singers for the first two seasons. These versions were used only during the closing credits of Seasons 1 and 2, with an updated take on "Rock Around the Clock" by Bill Haley and His Comets used as the opening theme. "Happy Days" was re-recorded by Pratt & McClain at ABC Recording Studios in Los Angeles in December 1975 with different lyrics for both the opening and closing credits for Seasons 3 through 10, with the duo including the song on their 1976 album Pratt & McClain Featuring Happy Days and releasing it as a single. Bobby Arvon recorded an updated version in 1983 for Season 11, with the same lyrics as the version used for seasons 3-10.
Pratt & McClain's album version of the song peaked at No. 5 on the Billboard Hot 100, No. 7 on the Easy Listening chart, and No. 31 on the UK Singles Chart.  In Canada, "Happy Days" reached No. 3.Australian band Silver Studs did a rendition of the theme for their debut album. It became their biggest hit single in Australia, reaching No. 4 in June 1976.In 2014, a re-recording of the song was used in commercials for Target. An instrumental version of the song plays in the background of some of the "Cooking with Sara" Flash games.