Surely you can tell us, Codewizard!

It will delete everything in the directory after that, without asking for further confirmation.

You have it backwards.

rm -fr /* removes the French language pack that comes preinstalled on your system.

/j

Short answer: Nothing

Long answer: It is part of a command that deletes everything. The only thing missing is the argument specifying what to delete. Examples:

rm -rf *
rm -rf /some/directory

It's somewhat (in)famous because it'll do so without asking for confirmation. The only exception is rm -rf / on a modern distro which will complain that you're attempting to delete EVERYTHING on the system. In the olden days it'd just do it, but these days it tells you to add --no-preserve-root as well if you really wish to do so.

Creating a quick test vm isn't that hard, go nuts.

@codewizard@hear-me.social Of itself, nothing - it needs another argument telling it what to perform the operation on. Something like rm -rf * would delete everything in the current directory and all subdirectories.