One slang term for basketball is "rock." Sentences including the term are "go ahead and shoot the rock," and "pass the rock to me." To "protect the rock" entails being careful when dribbling or otherwise handling the basketball, so the other team does not steal it.
The modern interpretation of basketball was created by Dr. James Naismith in 1891. It evolved from a game where dribbling was not allowed to an international sport with poles, backboards and nets. Basketball consists of two teams trying to outscore each other by putting the ball through their respective hoops at either end of a regulation-sized court.