How fast is fast?

It depends, I guess.

Usain Bolt, Jamaican running sensation, just hit his stride at 23 mph... and earned the title fastest human being. No has ever run faster. His 100 meter record time is 9.56 seconds... unless he has broken his own record, again, by the time you read this.

Well, Bolt IS fast... but if a cheetah was chasing him at 70 mph, he's a dead man. And if a peregrine falcon was diving on the cheetah at 200 mph, no way the cheetah is going to avoid an attack.

On the other hand, if a sloth was running from a sand dollar, the sloth would leave the sand dollar in the dust, so to speak, at 6 inches a minute. But a slow turtle could easily run down a sloth.

See what I mean?

How high is high? The world high jump record is a half inch above 8 feet... like leaping over a door frame with a running start. The pole vault record, using a standard 16 foot pole, is over 20 feet. Wow!

But a lowly flea can jump 100 times it's body height. For a 6 foot man, that would be a leap, from a standing position, of 600 feet... up to the 7th floor of most buildings.

Still, that is nothing for Superman who is able to leap tall buildings in a single bound.

So it's all relative. Unless you consider the speed of light. At 186,000 miles per second. That is absolute!

Impressive.