Start with the man pages. Running the command man followed by a space and then followed by the command you’re using will almost always give you a man page of the basics of how that command works. The fstab has its own man page too. An internet search “man fstab” or whatever command you’re interested in should also net many mirrors of the those man pages as well.

For me at least, it’s not that you’re asking questions. I answered, so obviously I’m sympathetic to confusion in this area. I’m just trying to encourage you to seek your answers in the documentation and manuals FIRST. The way your question was worded led me to believe that you had not read the manuals at all and were simply copying snippets of code and commands from some random question and answer style forum that did not teach you anything about the fundamentals of what those commands and code actually did. That’s fine too, lots of people started off that way, myself included. Reading the manuals gives you the context to step back and understand how those commands work and what they’re really doing. If you do, you’ll be much better able to troubleshoot your own problems, you’ll be able to ask better questions in forums like this, and you’ll get better and more useful responses.

With all due respect, RTFM. Mount and umount are two sides of the same operational coin. You mount the drive to use it and unmount it when you’re done. fstab is just a file system table used to remember and consistently apply the options used whether you’re mounting the drives manually or telling the system to do it at boot.

Deleting a line from fstab is not the same as unmounting, it is just a shortcut to tell the system how you want that drive mounted when you or the system run the mount command. Mount directories (usually the folders in /media/ or /mnt/ ) also do not get automatically deleted just because you “yanked the drive”. Again, those directories are just where your system is expecting to mount the drive. When the drive is mounted they will be the root path to its contents, when the drive is unmounted they will be empty but they still exist. If your planning on mounting the drive again leave them there. If you’re not planning on mounting them again, delete them.

If you’re not planning on regularly mounting a particular drive, it probably shouldn’t be listed in fstab and you should just run the mount command with the appropriate options (again fstab is just a table for remembering those options for the mount command).

Many desktop Linux distros are also capable of automatically mounting new removable drives in such a way that the user can access them and doesn’t have to worry about touching fstab or the mount directories.

I think the more nuanced take is that we should be making “piracy” legal by expanding and protecting fair use and rights to make personal copies. There are lots of things that are called piracy now that really shouldn’t be. Making “piracy” legal still leaves plenty of room for artists to get paid.