Sportsball is an activity in which people sport, usually, although not always, using a ball.
Sport involves setting up an arbitrary goal, giving this goal to two people or teams at the same time, and maximizing the conflict between the two teams in achieving that goal. For example, in many cases the goal is to get a ball into a net, but the two teams have different nets placed at maximal distances from each other; the progress of one team towards their net is balanced by equal and opposite regression on the part of the opposing team targeting their corresponding net.
There are a surprising number of variations on this theme, including bouncy sportsball, hitty sportsball, hammer sportsball, kick sportsball, hitty kicky sportsball, imaginary wizard sportsball, and many others.
As the basic dynamic is somewhat limited, many sportsball variants have complex rules to make them more intellectually engaging. These rules often target making different players on the team have different roles, having different rules apply on different parts of the field, and having rules about how much you are allowed to hurt your opponents.
One commonly touted aspect of sportsball is the 'spectator'. Spectator sportsball is simply a game that is prodigious enough to have more people watch it than play it. Many matches are so popular that they are televised, allowing for significant monetization. Spectatoring often involves knowing many things about the sports and the players, smalltalk targeting this information, yelling, drinking, eating, and sitting down for prolonged periods, often under very crowded conditions.
It is unclear who invented sportsball, or why.