Bash and Linux - Files and Directories

Before you begin, take a few minutes to check what you already know and how confident you feel. You will see the same questions again at the end of the module — this helps both you and us measure what you have learned. Click an option for every question and confidence rating, then click Next to continue.

Now that you can move around, the next step is to create, copy, move, and delete things. These are everyday commands - you will use them every time you sit at a terminal. The commands are short, but a couple are unforgiving, so we will cover the safety rails too.

• Making new folders and empty files: mkdir, touch.
• Copying and moving: cp, mv (and renaming).
• Removing: rm, rmdir, and why deletion in the terminal is permanent.
• Useful flags: -r recursive, -i interactive, -v verbose.

mkdir creates a folder in the current location:

$ pwd
/home/student
$ mkdir cohort_2026
$ ls
cohort_2026  notes.txt  scripts  vitals

List several folders in one command to create them all:

$ mkdir raw_vitals cleaned_vitals lab_reports figures

To create a folder AND any missing parents in one go, add -p. Without -p, mkdir refuses to create nested folders if a step in the middle does not exist.

$ mkdir cohort_2026/raw/vitals
mkdir: cannot create directory 'cohort_2026/raw/vitals': No such file or directory
$ mkdir -p cohort_2026/raw/vitals
$ ls cohort_2026/raw
vitals

$ mkdir test_folder
$ ls
$ mkdir -p study/raw/vitals
$ ls study/raw

touch creates an empty file. If the file already exists, touch leaves the contents alone and just updates the timestamp - occasionally useful in scripts. For now, think of touch as "make a new empty file".

$ touch patient_001.txt
$ ls -lh patient_001.txt
-rw-r--r-- 1 student staff 0 May 24 11:03 patient_001.txt

The 0 in the size column confirms the file is empty. You can pass several filenames at once.

$ touch a.txt b.txt c.txt
$ ls -lh

The shape is always cp SOURCE DESTINATION. The source exists; the destination is where the copy lands.

$ cp cohort_2026.csv cohort_2026_backup.csv
$ ls
cohort_2026.csv  cohort_2026_backup.csv

If the destination is a folder, the copy lands inside it with the original name:

$ cp cohort_2026.csv archive/
$ ls archive
cohort_2026.csv

To copy a whole folder you must add -r (recursive):

$ cp vitals vitals_backup
cp: -r not specified
omitting directory 'vitals'
$ cp -r vitals vitals_backup
$ ls
vitals  vitals_backup

mv has the same shape but MOVES instead of copying. The source disappears from its old location.

$ mv cohort_2026.csv archive/cohort_2026.csv
$ ls archive
cohort_2026.csv

There is no separate "rename" command - mv with a different destination name in the same folder is how you rename:

$ mv draft_cohort.csv cohort_2026.csv

mv does NOT need -r for folders. A folder and its contents move together in one step.

$ touch report.txt
$ cp report.txt report_v2.txt
$ mv report.txt archive.txt
$ ls

Deletion at the terminal is permanent. There is no Recycle Bin, no Trash, no Undo. Once a file is gone with rm, it is gone. Read that twice.

$ rm draft_cohort.csv
$ ls
(draft_cohort.csv is no longer listed)

To remove a folder and everything in it, add -r:

$ rm -r old_study

You will see rm -rf in online examples. The -f flag is "force" - it suppresses every prompt and ignores every warning. Avoid -f as a beginner. If you mistype the path, it silently obliterates whatever you mistyped.

Until your fingers are calm, get into the habit of rm -i. Bash will ask you to confirm each file:

$ rm -i patient_001.txt
rm: remove regular file 'patient_001.txt'? y

rmdir only removes folders that are completely empty. It is a safety net - if a folder still has anything in it, rmdir refuses, giving you a chance to notice.

$ rmdir scratch
rmdir: failed to remove 'scratch': Directory not empty
$ ls scratch
things_i_forgot_about.txt

$ cp cohort_2026.csv scratch.csv
$ ls
$ rm scratch.csv
$ mkdir tmp_dir
$ rmdir tmp_dir
$ ls

You have reached the end of the module. Try the same questions again — your answers here, paired with your pre-test answers, are how we measure what the module taught you. Answer every question and confidence rating, then click Submit and see results to view your score.

Here is how your post-test answers compare with your pre-test answers. The pre/post pairing is the most reliable way to see what this module actually taught you.