Darts grew up in English pubs, and the x01 games – above all 501 with double out – are now the standard both in the pub and in professional tournaments. The familiar order of the numbers 1–20 on the board is often credited to the carpenter Brian Gamlin in 1896, but that is not proven. The order is made so that a small miss is punished: next to 20 lie 1 and 5.
Sources: Darts