I love that this extends to the modern software keyboard where the shift key is now an actual arrow pointing to the metaphoric 'upper case'.https://twitter.com/roaringgirle/status/916714059965390848 …
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As far as I know without digging very deep, the arrow is solely a computer invention, plus started with European keyboards.
American keyboards said/say “Shift,” as did typewriters before – but very often, they left Shift and Shift Lock blank.
Here’s IBM 3276/7/8 from 1970s with great iconography all around, even for Insert and Delete.pic.twitter.com/7qQMY3kQdq
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