Started by Hannah Kim (@hannahk_ux) ·
why phone keypads and calculators are upside down from each other
5 sources · 18 min down the hole
How I got here
- Started with
- Why does a phone keypad have 1 at the top but a calculator has 7?
- Ended at
- “deininger 1960 bell labs pushbutton telephone study”
The Trail
- “why are phone and calculator keypads different” (google.com)
- Telephone keypad (en.wikipedia.org)
- Numeric keypad (en.wikipedia.org)
- Push-button telephone (en.wikipedia.org)
- “deininger 1960 bell labs pushbutton telephone study” (google.com)
What I came away with
Adding machines and calculators already had 7-8-9 on top. When Bell Labs designed touch-tone phones they tested a bunch of layouts on people (a 1960 human factors study by R. L. Deininger) and 1-2-3 on top worked well and felt natural. The two standards have just coexisted since. The story that they flipped it to slow people down seems to be made up.
Keep going
- why every cookie banner makes 'reject' harder than 'accept' · Hannah Kim · 6 sources
- 35mm photo film is movie film turned sideways · Hannah Kim · 6 sources
- the guy who invented infinite scroll regrets it · Hazel Park · 6 sources
- Clippy was built on serious research and everyone still hated it · Arjun Pillai · 6 sources