Frame of preference
The way that settings were done on the various Mac operating systems, down the ages.
Someone has suggested to me, without any sources cited, that DC Thomson was a supporter of the Nazi regime back in the 1930s (similar to the history of the Daily Mail, it seems).
I've gone looking for evidence of this claim and found nothing; I did find this though, which was kind of interesting.
From what I've been able to see on the Net, this is the tweet that first suggested using a hash and a symbolic name to group together tweets by subject.
I can remember, back in the day, using this and an external website to then search particular tags on Twitter. Sadly I forget the name of the website.