why a ledge on the key

on the piano keyboard, on the keys, near the edge under your palm, there's this little ledge protruding towards you.

why's that there? are there pianos don't have that?

thanks.

Xah
http://xahlee.org/PageTwo_dir/more.html

Hello Xah,

That little ledge is a tradition. When ivory veneer or 'wafers' were used for keytops, the top part covered the joint between the top and the front. There have been some pianos that simply curve the plastic veneer over this point. This is called a 'waterfall' design because it looks a little like one.

(if you REALLY use your imagination)

Richard Galassini Cunningham Piano Co Phila,. Pa. 1 (800) 394-1117 URL:http://voce88.tripod.com/richspianopage