Those characters are just as “charactery” as anything else you type– they take up space, they’re copy and paste-able, you can give them a point size– but they’re invisible, and they don’t print. Microsoft Word on the Mac has a nice feature that lets you show invisible (non-printing) characters such as returns, tabs, and spaces. Command-8 to show them, Command-8 again to hide them. There’s a keyboard shortcut for toggling invisible characters (like paragraph marks, and spaces, and tabs) in Microsoft Word on a Mac and as far as I know it’s worked in every version, since the very beginning.
