Remember in elementary school we (meaning us American pig-dogs) used those little rulers that had twenty centimeters on one side and about eight inches on the other? Ever wonder how somebody figured that one out? Since one centimeter is exactly the distance that a ray of electromagnetic energy travels through a vacuum in precisely 3.33564095 x 10^-11 of a second, do you think somebody measured the space traveled by some ray of light and marked it on the plastic bar? That'd be some kind of lightning fast stopwatch.
And how about the inch side? Did they use the old school method of determining an inch by measuring the diameter of three average sized barleycorns or did they just get lazy and use the new version, which bases the inch on centimeters? Yep, that's right, inches are now just a thinly laid veil laid over 2.54 cm. You've been using the metric system for years and you didn't even know it.
That's because the centimeter has been declared unit of measurement most likely to succeed by white-coated know-it-all scientists. If only it were bigger, then perhaps it could be a standard measurement, like those meter/kilogram/seconds kids. But being metric makes it feel better about having its dad, Mr. Meter, as the head measurement in the SI system. If you're still using the inch side of your ruler to do your calculations, you might as well stop reading now and continue presenting your new theory of spontaneous generation to your favorite Barbie dolls. Back in the day, when folks appreciated the subtlety of the csg system (centimeter/gram/seconds), centimeters got to be the unit of capacitance, too. Capacitance is the ratio of charge to voltage on the body, the body being whatever poor sap got fried trying to scale your electric fence and eat your prized hog. Not enough centimeters on that one, ayuh.
Centimeters took over the airwaves, too. If you tune your FM dial to right about the middle, 99.9 or 100.1, take your pick, you'll be listening to a 300-cm wavelength radio wave. But don't hate the centimeter for the crappy sound you hear, that ain't its fault. Don't kill the messenger if you hate the message, baby, maybe you just need a few more or a few less centimeters on your waves. Yeah. Doesn't that feel better? | 
