A 90-second bash tour (for people who got dropped into this site)

A 90-second bash tour

May 18, 2026 · 4 min read

If you landed here and the terminal feels alien, this is for you. Bash is the shell — the program that turns what you type into what the computer does. It’s been around since 1989 and is still how most engineers move around a unix-ish machine.

You only need six commands to get the gist.

1. pwd — “where am I?”

The shell always has a current directory (a folder it’s sitting inside). pwd prints it.

$ pwd
/home/michael

2. ls — “what’s here?”

List the contents of the current directory.

$ ls
about.md  blog/  contact.md  projects/  resume.pdf

Add -l to see details (size, modified date).

$ ls -l projects

Folders end with a / in our prompt, files don’t.

3. cd — “go somewhere”

Change directory. The shortcuts:

• cd projects — step into projects/
• cd .. — go up one level
• cd / — jump to the root of the filesystem
• cd ~ — jump to home folder
• cd — same as cd ~

So cd projects/duke-dine walks two levels down in one go.

4. cat — “show me this file”

Print a file’s contents.

$ cat about.md
$ cat projects/duke-dine/README.md

In this site, cat’ing a known file opens its viewer window. The menu bar does the same thing in fewer keys, but cat is what feels like home.

5. tree — “show me everything”

Renders the whole folder structure as an ASCII tree. Useful when you’ve forgotten where something lives.

6. Tab and ↑ — “type less”

These aren’t commands, but they save more time than any of the above:

• Tab — autocompletes a file or command name
• ↑ / ↓ — walk back/forward through your history
• Ctrl+L — clear the screen (or type clear)
• Ctrl+C — cancel the line you’re typing

If you type cd pr then Tab, the shell will fill in cd projects/. If two things match the prefix, hit Tab twice to see options.

Now you try

Close this window and paste these one at a time into the terminal:

1. pwd
2. ls
3. cd projects
4. ls
5. cd duke-dine
6. cat README.md
7. cd ~
8. tree

That’s enough to make any portfolio cat’d, ls’d, cd’d, and generally seen.

Type help in the terminal anytime to see this site’s specific commands.