The Scottish Professional Football League (SPFL) is the top professional football league in Scotland. It was formed in 2013 when the Scottish Premier League and the Scottish Football League merged. The league consists of four divisions: the Premiership, Championship, League One, and League Two, with a total of 42 teams competing. The SPFL operates on a promotion and relegation system, meaning that the best-performing teams can move up to a higher division, while the lowest-performing teams may drop down. The league is known for its passionate fan base and historic clubs, including Celtic and Rangers, which have a long-standing rivalry.