Rugby football is very different from American football.
took time off work to play the sport, thus making rugby league the first code to turn professional and pay players. It was a hundred years later in 1995, following the 1995 Rugby World Cup in South Africa, that rugby union turned fully professional. The respective world governing bodies are World Rugby (rugby union) and the Rugby League International Federation (rugby league). 
Rugby football was one of many versions of football played at English public schools in the 19th century. Although rugby league initially used rugby union rules
star code converts can have a substantial impact on the games. For instance, Dally Messenger's defection from rugby union to rugby league was considered a pivotal moment in the establishment of the latter over other codes in Australia.
Globalisation is increasing the opportunities for players to transfer to different countries and to different professional sports, including the forms of football.
From American football.
From American football American football to Canadian football.
American football and Canadian football are very similar gridiron codes; talented Canadian youth players are often recruited