The telephone company (the *real* telephone company, before that Communist b******d, judge Harold H. Greene, got his politically motivated mitts on it) spent a fair amount of money determing how people remembered phone numbers.
Back in the days of rotary phones (I doubt but a few of you are old enough to have used them. Perhaps you've seen them in museums and such), when phone numbers were shorter, they used a couple of letters, and the digits, like 'BR-549', or some acronym for the letters ('Slick Willy-666' for SW-666).
When semi-modern (non-VoIP) phones (ones with DTMF pads) were developed, and a standard length number format was settled on, they spent much more money learning that people grouped digits to remember them, and the 3/3/4 method of expressing a phone number came about. Along with this study came the layout of the dialing pad itself, with 1 at the top left. This came out slightly ahead of another possible payout, more like a common calculator would later use. It was determined that for the purposes of remembering the numbers, the TL1 (TopLeft1) layout aided memory better than then the BL1 (BottomLeft1) layout.
For some reason, the Europeans never took this to heart. Since it was a lot harder to get various countries, each with their own switching equipment ranging from pre-crossbar-1A systems up to the latest switches, to all upgrade together, the European phone numbers range from 4 to 13 digits, sometimes even within the same country. Imagine trying to work with that...
--Chris
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