Have you observed that the keypads of phones and calculators are reversed?
And if you’ve been finding an answer as to why the numbers are from bottom to top on the calculator and top to bottom on the phone, we have an answer to that.
The answer lies in mechanical cash registers which were constructed in such a way that the number “0” is at the bottom.
This is because “0” is the most used number and it made complete sense to keep it there so that it is accessible to the fingers easily.
And then when calculators made their appearance, they followed the same rule.
And the calculators still use the same rule. But the phones have changed their layout thanks to Bell Telephone Company.
The engineers of Bell Telephone company couldn’t make their mind as to what keypad layout they should implement.
They were confused between 5×2 matrix and 3×3 matrix. To resolve this issue, they called many people to use the keypad and let them know about the design they were most comfortable in.
The engineers came to the conclusion that the number 1-2-3 would be on top.
And that is how the entire keypad system was decided.
Wow, I feel a little smarter after knowing this! What about you?
Source: Interesting facts