#Steganography in copied text! You can tell there's invisible text by arrowing through it. The cursor pauses at each hidden character. Or, when pasting into Word, the words with characters inserted are highlighted by spellcheck. I realized Word does show non-printing characters if you tell it to. Click on the paragraph symbol to do this. Hiding this kind of text will go under almost everyone's radar though - you have to know it's there, before you would think of checking. https://medium.com/@umpox/be-careful-what-you-copy-invisibly-inserting-usernames-into-text-with-zero-width-characters-18b4e6f17b66
@shel education should be free. Not because it helps the student (which is a nice side benefit) but it improves society by reducing other costs, such as training employees, etc. Critical thinking skills in the general population would REALLY improve US society. I'll get off my soapbox now. Heh.