Actually, they left it where it was originally. (It’s swapped on US style computer keyboards, although the typewriter retained the quote in that position.)
Why the at symbol was given a more prominent place on the keyboard is left as an exercise for the reader.
I like that over the 3 they replaced the pound sign with…a pound sign.
What is above the single quote and what is it used for? EDIT: The one over the TAB key.
Actually, no. It’s the “broken bar” sign (¦), which is a different character from the “or sign” or “pipe” (|). If you look, the normal solid pipe also appears on the UK layout, as the shift of backslash, located next to the Z key.
ETA:
The normal pipe is ASCII 124 (dec), the broken pipe is extended ASCII 166 (dec)
When did the at-sign migrate to above the two? I remember on computers in the 80s (at least on the Commodore), it was shift-two. And is it only on the US layout that it’s above the two?
ETA: It looks like the Apple IIe had the at-sign above the two already. Hmm…Wonder who the first was to put it there.
ETA2: Apple II plus had it the quotes above the two.