Key components of games are goals, rules, challenge, and interaction. Games generally involve mental or physical stimulation, and often both. Many games help develop practical skills, serve as a form of exercise, or otherwise perform an educational, simulational, or psychological role.
Many sports require special equipment and dedicated playing fields, leading to the involvement of a community much larger than the group of players. A city or town may set aside such resources for the organization of sports leagues.
Popular sports may have spectators who are entertained just by watching games. A community will often align itself with a local sports team that supposedly represents it (even if the team or most of its players only recently moved in); they often align themselves against their opponents or have traditional rivalries. The concept of fandom began with sports fans.
Stanley Fish cited the balls and strikes of baseball as a clear example of social construction, the operation of rules on the game's tools. While the strike zone target is governed by the rules of the game, it epitomizes the category of things that exist only because people have agreed to treat them as real. No pitch is a ball or a strike until it has been labeled as such by an appropriate authority, the plate umpire, whose judgment on this matter cannot be challenged within the current game.
Certain competitive sports, such as racing and gymnastics, are not games by definitions such as Crawford's (see above) – despite the inclusion of many in the Olympic Games – because competitors do not interact with their opponents; they simply challenge each other in indirect ways.