Superhuman Speed is the ability to move much faster than the average member of their species, some near or at the speed of sound, or even faster.
However, this power is not without any ill effects, as it can strain the body, although some users may be resistant or even immune to the effects of high speed travel, including friction, g-force, inertia, etc.
Notable Characters that have superhuman speed[]
For a list of all Characters with Superhuman Speed see here