The KBO League (Korean: KBO 리그), officially as Shinhan Bank SOL KBO League for sponsorship, is the highest level league of baseball in South Korea. The KBO League was founded with six franchises in 1982, and has expanded to ten franchises. The KBO League is the most popular sports league in South Korea. The Kia Tigers are the most successful team, having won 11 out of the 38 championships. In comparison with American Major League Baseball, ESPN reports that the KBO level of play "appears to be somewhere between Double-A and Triple-A, on average, though the best players are more likely to be MLB-quality than your typical Double-A league." Historically, the KBO is known for its vocal and exuberant fan base, as well as the widespread practice of bat flips (ppa-dun (Korean: 빠던), a portmanteau of the "first syllables of the words for 'bat' and 'throw'") by hitters after stroking what they think will be a home run. In the KBO, the bat flipping tradition dates back to the 1990s.