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C uses "&" for the address-operator because 'ampersand sounds like "address"'
(softwareengineering.stackexchange.com)
Fascinating, but something that wasn't brought up was the limited number of characters that were more or less guaranteed to be on anyone's keyboard. The IBM Selectric II and later the PS/2 would both become so ubiquitous as to standardize both the layout, and, in the case of the PS/2, the connector for computer keyboards.