The whole story started when I tried to sign a LibreOffice document. When you belive the internet, document signing is inbuilt into LibreOffice.

Some numbers from the Nature 2019 graduate survey are discomforting.

First, some definitions: UV-C (100/200-280/290nm, short-wave, hard UV), UV-B (290-315nm, medium-wave, intermediate UV), UV-A (315-400nm, long-wave UV, soft UV, "black light")