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Starting with a piano keyboard where A-L were on the black notes and M-Z on the white below them in reverse order

Then the vowels were moved to the top row These letters still fit that pattern eyuio adfghjkl mnvxz

I and O were near 9 and 8 because they were also used as 1 and 0 to save keys, and people wanted to type 1870 etc easily.

A was swapped back to the middle row for ease of use, everything else was pretty much to avoid patents of other layouts

QWERTY stuck because typing classes were invented and they first used QWERTY