Horsepower vs. Torque

Consider you have a wheel that you're moving by hand. How much energy does it take to move the wheel around one revolution (i.e. all the way around once, back to the starting position)? That's what torque describes. Now consider if you want the wheel to turn as fast as it can. You now have to put in extra energy, so that the wheel turns multiple times as fast as it can. That's what horsepower describes. Both torque and horsepower are describing energy, but with torque it doesn't matter how long it takes for the energy to be applied, and with horsepower it does matter.