Probably an unnecessary reply I make here given the quality responses above, but my two cents anyway: As said, if you graph torque & horsepower simultaneously you will see a certain rpm where the curves cross. Torque, I believe, can be called "engine twisting power". For example, a 1967 Mopar 440 wedge motor with 375 hp, had very good torque at lower rpms (in most, if not all engines, maximum torque is seen to rise, then drop, sooner than horsepower. This is why the 440 could, if 440 is stock hi-performance, in the same chassis/transmission/gear ratios, etc, would beat a 426 hemi in the quarter mile. The hemi developed it's torque later, but above 3000 rpm the hemi is gaining on that 440. Couldn't beat a 440 in the quarter mile, generally, but if the race were a half mile, the hemi has come into it's own and devastates the 440. This difference in the quarter mile vs the half is because the hemi has more horsepower. Many may differ, perhaps with good reason, but it is a fair intuitive statement to make that "torque determines acceleration, horsepower determines top speed".