Long S
en.wikipedia.org
en.wikipedia.org
I read some place it's because google's character recognition automation interprets the long S as an 'f' instead of an 's'
Survived from through to late 1700s whilst only against the hand-powered press, then as soon as industrial presses (steam powered) appear circa 1800 and mass printing was now possible (double-output with far lower human effort being input) it dropped off.
Still doesn't wholly explain it though. If it was seen as a valid character you would expect that the symbol would've been in the charset and have been used in print too.
“Dear Mr. Jones: I am pleaſed to reply to your meßage of Tueſsday laſt, requeſting my ſervices as a ſoft-ware engineer...”
Did not know that.
The limit of their diminishing IS the Reimann integral. So it makes sense to use 'S' for sum.
Big-Sigma (∑) is used for summation in general, and Big-pie (∏) for products.
The Nazis banned Fraktur, probably because Hitler didn't like it, and we never re-introduced it. As an irony of history, for some people Fraktur now carries connotations of the Third Reich. (See https://en.wikipedia.org/wiki/Antiqua-Fraktur_dispute)
I have a few old books in Fraktur. Faust and translations of Shakespeare's plays.
P.S. For my resume, my name only has the wrong kind of s.