Phone V Computer Keypad…WHY?

Phone V Computer Keypad…WHY?

Oct 16, 2015

Ever wondered why Computer Keypads are the complete opposite to Phone Keypads?

There are a few theories but here are my top 2.

The first one is: It just makes sense for the 1 to be at the top left like on a phone as this is the way we read, left to right, top to bottom. But then why are computers upside down?

The second is: The touch-tone phone was being developed in the late 50’s, this is after basic calculators and adding machines. As anyone who is an accountant or book keeper would know, you become quite proficient and fast at hitting these keys (in the 3×3 layout). So Data entry clerks were literally too fast for the number’s “tones” to register.

But then why the 3×3 layout? It was during this era when we were making the transition to 3×3 as opposed to the previously use straight line of numbers….

I know I have simply given you more to think about so here are the answers to the new questions, or theoretical answers at least…

Why 3×3? Basic ergonomics, it’s just simpler to use, especially at speed. The index finger using the first column. The next two fingers using their respective columns and the thumb using the 0 exclusively, as the pinkie does with the enter button. Other layouts were tested including 2 rows of 5 numbers but the 3×3 worked the best.

Why are PC’s upside down? The modern-day PC layout is based on the original 3×3 adding machine layout.  With the 0 being use by the thumb, it was placed at the bottom of the keypad (nearest your thumb) as were the decimal and the enter buttons. This, combined with Benford’s Law or First-Digit law means placing the 1 at the bottom left meant a large number of entries could be done using the bottom 2 lines of the keypad. As phone numbers don’t conform to Benford’s law because of the area codes then this wasn’t really a consideration when developing phone keypads.

For those of us that work in admin and accounts having to switch between the 2 layouts is still a pain in the but…. But now you know why…

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