In soccer curving the soccer ball is one of the many ways you can put the ball passed the goalie and into the net. Watching a player like David Beckham kick the soccer ball and put curve on it you will see the how far the ball curves back inside and into the net with incredible accuracy. As this is the process of the air dragging against the ball while it soars through the air.
When the ball is spinning, the air tends to follow a longer path around one side than the other, because it's dragged along by the ball's turning surface." Air following the longer path bends more sharply, resulting in a dramatic drop in air pressure on that side of the ball. The ball is pushed toward the low-pressure side. A similar drop in pressure over an airplane's wing is the source of lift that supports the plane. Now when you see someone kick a soccer ball or throw a baseball and it curves you know why is does that, and now can explain the process to other people.