Piano/synth keyboard layout question

This question probably has an obvious answer, but I've never studied piano and I don't know much about it.

Here's the thing: I've noticed that, if a synth or midi controller has fewer than the piano-standard 88 keys, the number is generally some multiple of 12, plus one. 25, 37, 49, 61...all multiples of 12 with one key added.

This makes sense to me: If you have a multiple of 12 keys, plus one key, the highest key will be the same note as the lowest key, but some whole number of octaves higher. Makes it nice and even; and you don't find yourself moving up the keyboard and suddenly thinking "Dang; I've run out of keys on my way to the tonic."

So...how come a piano -- or a full-sized synth or midi controller -- has 88 keys? That's not one more than a multiple of 12; it's one more than 87! The highest key on a piano must not be some whole number of octaves higher than the lowest key. So a piano has a whole number of octaves, plus a few keys tacked on the end.

What's the reason for this? Does it have something to do with playing in multiple keys?

from this site: http://www.austinpianoworks.com/faq.php

Why does the piano have 88 keys? Pianos developed over the centuries since 1700 to accommodate the needs of the musical culture in which they thrived. Harpsichords have 60 keys. As the new pianoforte (“soft-loud”) swept Europe in the late 1700’s the keyboard expanded now that it was able to be more resonant in greater and greater musical ranges. The expansion stopped at 88 notes because it was generally determined my musicologists and the public that the low A, which vibrates at 27.5 beats per second and the highest C, which vibrates as a an amazing 4186 beats per second, were about as much as anybody needed. Plus, most of us can’t distinguish one note from another beyond those two extremes.

Interesting!

Thanks for the link.

Some of the older pianos only had 85 keys which was from C to C or A to A depending on manufactuer. Those low notes played on a nine foot concert grand can really help food digestion. Have fun, Wayne