user@user-ThinkPad-T430:~$ sudo mount /dev/sdb1 /mnt/tmp
mount: /mnt/tmp: mount point does not exist.

As a side note, if you were to mount a file system on a device to a directory that already had contents, the next time you viewed the contents of that directory, you would see the mounted-device's file system, and it would appear that all the old contents are missing, or have been deleted: they're not. The mapping to files for that directory got changed by the mount command to now look at a separate device. As soon as you unmount the device from that mount point, the old contents are back. So that is scary cause it looks like stuff is gone, and because you wouldn't want to mount over a part of the running file system that is in use by the linux system, because your system wouldn't be able to find essential components that it uses.

sudo mkdir -p /mnt/tmp

• You already know what sudo does.
• "mkdir" is the command-line shell's shorthand for "make directory"
• The "-p" flag instructs the make directory command to make any parent directories if they don't exist, in this case, /mnt: if /mnt didn't exist, then it would have to be made first, before making /mnt/tmp, and the -p flag tell is to do that. You could do it like "/sudo mkdir -p /mnt/molly/loves/linux/tmp" and the -p flag would create the entire nest of parent directories that contain the new directory, tmp, that you are making. But that many nested directories was just to illustrate the -p (parent directory) flag, and you don't really need to do it to create an unused directory to be your mountpoint.
• And of course the "/mnt/tmp" is the path to the directory you want made

And another side note about feeding paths to console commands: whether or not you start your path with a forward slash, "/", is extremely extremely important, crucial, vital, essential, and a detail that must always be closely checked:

• if the "/" is present, the console command is instructed that, in order to find where in the file system it should operate, it should start at the beginning, the highest-level directory, the root file, represented by "/", which I think of as the entire filing cabinet; and then the command proceeds to focus on the first directory after the slash, and so on. Pathnames like this that start with this slash are called absolute pathnames.
• Without that initial "slash" the console command begins operation from whatever directory is in focus (called the working directory). Pathnames without the initial slash are called "relative pathnames" because they are relative to the working directory. When you first open up a console terminal, the working directory defaults to your user's home folder, /home/youruser. However, this path is typed so frequently, that a shortcut has been assigned to it: "~". In your screenshot, your prompt at your console terminal looked like this:
  Code:

  user@user-ThinkPad-T430:~

  This prompt tells you that you are logged in as user user, to host user-Thinkpad-T430, to this working directory: /home/user! To save space in command-line prompts and typing paths, it reported the /home/user as a tilde. Thus you can use a "~" and "/home/user" interchangeably when typing paths to console commands.

sudo mount /dev/sdb1 /mnt/tmp

sudo cd /mnt/tmp
sudo ls -lah

• "-l" instructs list to use an entire line for each file in the contents, and to use long format, which is handy because, in addition to the name of the file, it also displays which user owns the file, which group owns the file, the permission settings on the file, when the file was last modified, and the size of the file, which is why it needs an entire line.
• The -a meens to list all files, including hidden files (files whose names start with a dot, are not normally visible when viewing contents of directories, unless this "-a" flag is present), and the
• "-h" tells the list command to display file sizes in units suitable for human comprehension, so to report 10000 bytes as 1M.

Quote:

Originally Posted by hazel ...Every file and every directory on Linux is owned by a user and a group. The user in this case is you (called "me" in this display but the actual name is the name you log in with). The group that you belong to (and that all your files belong to by default) was assigned by the system when you created your user account. Most modern Linux systems create a unique group for each user with the same name, but some have a group called user or users for all personal users. If you click on the arrow, you should see what group names are available.

Quote:

Originally Posted by hazel When a file is created, it belongs to the user who created it. If you created it as root, then it belongs to root and to the root group. But if you created it as molly and then become root, the file's ownership does not change unless you change it. And only root can change the personal owner of a file.

It recognizes me, logged on as "user", as the owner of the stick,
with full Read-Write Permissions.

"Group" "user" is locked out: Access only.

And with this, I am locked out: "user" (the one & only user account ever, who is (& seems to be recognized as) "root".