The Super Bowl is the annual championship game of the National Football League (NFL) played annually between the champions of the National Football Conference (NFC) and the American Football Conference (AFC). The game is the culmination of a regular season that begins in the late summer of the previous year. Normally, Roman numerals are used to identify each Super Bowl, rather than the year in which it is held. For example, Super Bowl I was played on January 15, 1967, following the 1966 regular season. The sole exception to this naming convention tradition occurred with Super Bowl 50, which was played on February 7, 2016, following the 2015 regular season, and the following year, the nomenclature returned to Roman numerals for Super Bowl LI, following the 2016 regular season.