I saw your 'discussion' and registered to stop you beating the textual crap out of one one another.
Please learn some history and all will be revealed.
Football means the games derived from English games played in the mids 1800's. There are many types of football, american football, irish (gaelic) football, association football, rugby football etc. All these games are played with footballs - thus the name.
Using the word football means the predominant form of the game in the users context. So if an American says football - they mean Amercian Football, an Australian will mean Australian Football. Most Europeans aren;t aware that their game is actually called Association Football and insist that it is called only 'football' to the detriment of all the other codes.
If you learn the history of the development of the games, rugby was one of the first form to actualy have some rules written, then Australian football and later Association Football. American Football was derived from Rugby football in the 1880's.
All those forms of football were very similar back then. All were rough and had lot's of contact. The original 1863 rules of Association Football allowed all players to catch the ball and take a free kick (a feature that still exists in Australian football).
Each of these games have evolved since then. Association Football eliinated the roughness and football handling, American football focussed on play strategies etc.
I recommend the Wikipedia article on the history of Football
Football - Wikipedia, the free encyclopedia
All these games are football. If you are in an international forum like this, you need to explicitly define which form of football you are talking about.
Personally I like International Rules Football that is played between Ireland and Australia. It's probably closest to the type of football played 150 years ago.