Speed, is the rate at which someone or something is able to move or operate. Velocity is the speed at which someone or something is able to move or operate. Velocity, is important when Nascar drivers depends on their cars in order to quickly get them to the finish line. Speed is important when operating motor vehicles. When driving speed can be very harmful. The act of speeding can cause life-threatening disasters and could also cause someone to die, due to the loss of control. Even though many may not notice it, we use speed more often than we may think that we do. For instance, I use speed everyday when trying to get to work on time. I procrastinate and have to rush in order to make it on time.