Why are the 1-2-3 on top of a telephone key pad and on a computer they are on the bottom ?

Answer 1

The following was originally reported on ABCNews.com. It appears to explain the answer with some authority:

"The real answer seems to lie in a study conducted at Bell Labs titled “Human Factor Engineering Studies of the Design and Use of Pushbutton Telephone Sets.” Published in the July 1960 issue of the Bell System Technical Journal, the report says that researchers tested a number different layouts including the three-by-three matrix with the zero at the bottom; versions with two rows of five numbers, arrayed either horizontally or vertically; and circular configurations with numbers laid out in clockwise and counterclockwise fashion. The study concluded that the three-by-three version with 1-2-3 in the top row was the easiest for people to master.

"There was another reason as well. When it came time to match letters of the alphabet up with the numbers, putting 1-2-3 across the top made a lot more sense because it was the most natural way to get ABC in the top row. If 7-8-9 had been at the top, one of two things would have happened — the letters and the numbers would have run in opposite directions, or PRS would have been the first set of letters. Either arrangement would have seemed very odd, indeed.

"All this raises another interesting question. When Bell Labs began exploring keypad layouts in the late 1950s they contacted all of the leading calculator manufacturers to find out why they had chosen to put low numbers at the bottom and high numbers at the top rather than the other way around. The answer, apparently, was a big shrug. It turns out that decision was largely arbitrary: no one had done any research about which layout was most convenient for users. Still, when it came time to place a numeric keypad on a computer keyboard, the calculator model with 7-8-9 at the top prevailed."

Answer 2

google is your friend. i found this in 20 sec after reading your post.
http://www.google.com/search?hl=en&safe=off&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&hs=lYh&q=why+are+numbers+on+keyboard+opposite+phone+pad+layout&btnG=Search

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