Flyball is a dog sport where teams of four dogs race against each other over a line of hurdles to a springloaded box, "catch" a tennis ball from the box and then race back to their handlers with the ball. The fastest team that runs without any errors wins.
The course consists of the start line, 4 hurdles spaced 10 feet apart and a box. The start line is outfitted with a line of red, yellow, and green lights, similar to what you would see at a drag race. A large space behind the course (runback area) allows the teams to position themselves and give their dogs a running start.