Wikipedia - K League 2

The K League 2 (Korean: K리그2) is the men's second-highest division of the South Korean football league system. It is contested between thirteen professional clubs and operates on a promotion and relegation system with K League 1.

History

In 2011, the original K League announced a plan to begin a promotion and relegation system between the K League and a proposed second division. The K League then took steps to create the new second division, mainly with the addition of a split-system during the 2012 K-League season in which the bottom clubs are placed in a competition for safety with the last placed club being relegated to the new second division (originally it was going to be two clubs relegated but the withdrawal of Sangju Sangmu meant only one would be relegated).

The second division was going to get the name of K League, and the original K League's name was changed to K League Classic along with the new logo. However, the change caused some degree of confusion and controversy, and on 11 March 2013 the official name was changed to K League Challenge. On 22 January 2018, its name was once again changed to K League 2.