在足球场上，如果足球滚出边界就会被判为界外球，由对方球员双手把球掷回球场，同时，双脚後跟不能离开地面。这里我们谈的“界外球” 是泛指绿荫场地外，一切有关足球的行为。与此行为相关的产业统称足球产业，它的兴起有些出人意料，当更多的人关注球场上的比赛时，另一些人 In the football field, if the football out of the border will be sentenced to extra-world ball, both players throw the ball back to the court with both hands, at the same time, the heel of both feet can not leave the ground. Here we talk about “outside the ball” refers to the green shade outside the venue, all the behavior of football. The industries associated with this activity, collectively referred to as the football industry, have some unexpected developments. When more people are concerned about the games on the court, others