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I suppose keyboard layout issues originated with Victorian typewriters
The ' told the type-setter or reader an accent, opening quote, closing quote or single prime like for feet or minutes (time or angles). The Backspace key allowed to to be placed above any character.
O also was used for 0 (no 0 after the 9)
I was also used for 1
The " meant open quote, close quote, ditto or double prime (inches or seconds).
The # was often used as the Any Currency, but L backspace - or = for £ or Lira.
Oddly there was often an @ for prices. 6 loaves @ 2d
In 1928 the Teletype was added. It used only 32 symbols, but one meant alternate, so 62 total, later became Telex and had 7 bits (127 characters. all holes meant null or erased as thus a mistake could be erased). Prior to that it had been a keyboard to tape for sending morse by telegraph or radio. Some characters had special meaning:
BS: Backspace, Move print head back one to allow overprint
LF: Linefeed, Move paper one line without moving head
CR: Carriage Return, Move head to left Margin without advancing paper.
HT: Tab, move head right, a fixed number of times, or to next column
VT: Move a number of lines.
FF: Form Feed. Move about 66 lines. Not eject page, because a continuous roll was used.
BELL: Ring a bell or buzzer!
DEL: Usually do nothing, but if keyboard driving a tape punch it would reverse and put all holes, which would be ignored at receiver.
It was only with Terminal Screens that BS became erase prior and DEL became erase next.
EOT: End of transmission.
In the mid 1940s to 1970s computers used Teletypes for Input/output. So from 1960s the terminal screens used much the same keyboard layout as a teleype/teleprinter in 1928.
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