How to Use the Terminal - Linux Command Line Basics

How to Use the Terminal - Linux Command Line Basics
Reading time: About 10 min Difficulty: Beginner

"A black screen with white text all over it, and I have no idea what's going on..." Are you avoiding the terminal like this? In this article, through a dialogue between Linny-senpai and Lina, let's learn the basics of terminal operations together.

1. Introduction: What is a Terminal?

Lina: Linny-senpai, I opened the terminal, but... there's a black screen with some text displayed, and I don't know what to do...
Linny-senpai: Don't worry, everyone feels that way at first. Let me explain what a terminal is.

What is a Terminal?

A terminal is an application for sending commands to your computer using text. Instead of clicking with a mouse, you operate by typing commands (instructions) on your keyboard.

Lina: It seems harder than using a mouse...
Linny-senpai: You might feel that way at first. But once you get used to it, you can work faster and more accurately than with mouse operations. For example, when renaming 100 files, what takes an hour with a mouse can be done in seconds with the terminal.
Lina: Wow, that's such a big difference!

Benefits of Using Terminal

  • Fast: Faster than mouse operations once you're used to it
  • Automatable: Can repeat the same tasks automatically
  • Precise: Can specify detailed settings exactly
  • Essential for servers: Many servers don't have a GUI

2. Understanding the Prompt

Lina: There's user@computer:~$ displayed on the screen. What is that?
Linny-senpai: That's called a prompt. It's a signal saying "please enter a command." The prompt contains important information, so let's learn how to read it.

Prompt Structure

yamada@penguin-gym:~/Documents$
Part Meaning
yamada Username (who's currently logged in)
@ Separator
penguin-gym Computer name (hostname)
: Separator
~/Documents Current location (directory)
$ Regular user indicator (# for root)
Lina: What does ~ mean?
Linny-senpai: ~ represents your home directory. The home directory is like your "personal room" for each user, which means /home/username.

Special Symbols to Remember

Symbol Meaning
~ Home directory
. Current directory
.. Parent directory (one level up)
/ Root directory (top level)

3. Your First 3 Commands

Lina: There seems to be so many commands to learn, I'm worried...
Linny-senpai: Just learn 3 commands at first. pwd, ls, and cd. With these three, you can find out "where you are," "what's here," and "where to go."

pwd - Check Where You Are

Linny-senpai: pwd stands for "Print Working Directory" and displays the directory you're currently in.
$ pwd
/home/yamada
Lina: Oh, so I'm in /home/yamada right now!
Linny-senpai: Exactly. If you ever get lost, just type pwd and you'll immediately know where you are.

ls - List Files

Linny-senpai: ls stands for "list" and displays the files and folders in your current location.
$ ls
Documents  Downloads  Pictures  file.txt
Lina: Does this mean there are 4 folders?
Linny-senpai: Documents, Downloads, and Pictures are folders (directories), and file.txt is a file. Add the -l option to see more details.
$ ls -l
drwxr-xr-x 2 yamada yamada 4096 Jan 24 10:00 Documents
drwxr-xr-x 2 yamada yamada 4096 Jan 24 10:00 Downloads
drwxr-xr-x 2 yamada yamada 4096 Jan 24 10:00 Pictures
-rw-r--r-- 1 yamada yamada   52 Jan 24 10:00 file.txt

cd - Change Directory

Linny-senpai: cd stands for "change directory" and moves you to a different directory.
$ cd Documents
$ pwd
/home/yamada/Documents
Lina: So cd Documents got me into the Documents folder!
Linny-senpai: That's right. To go back up one directory, use cd ... To return to your home directory, use cd ~ or just cd.
$ cd ..      # Go up one level
$ cd ~       # Return to home
$ cd         # Return to home (short form)

4. Useful Shortcuts

Lina: Isn't it tedious to type the full command every time?
Linny-senpai: Great question! The terminal has convenient shortcuts. Tab completion and history navigation are essential.

Tab Completion (Super Important)

Linny-senpai: If you type part of a command and press Tab, it will auto-complete for you.
$ cd Doc[Tab]
# Completes to: cd Documents/
Lina: Wow, that's convenient! It will also reduce typos.
Linny-senpai: Exactly. When there are multiple options, press Tab twice to see a list.

Commonly Used Shortcuts

Shortcut Function
Tab Auto-completion
Up Arrow / Down Arrow Browse command history
Ctrl + C Cancel running command
Ctrl + A Move to beginning of line
Ctrl + E Move to end of line
Ctrl + U Delete from cursor to beginning of line
Ctrl + L Clear screen (same as clear)
Lina: Should I remember Ctrl + C?
Linny-senpai: Absolutely! It's the emergency escape button when a command won't stop. Remember: when in trouble, press Ctrl + C.

5. Common Errors and Solutions

Lina: I typed cd Documents and got "No such file or directory"...
Linny-senpai: That's a common error. There are several possible causes, so let's look at them together.

Error 1: No such file or directory

$ cd Documents
bash: cd: Documents: No such file or directory

Causes and Solutions

  1. Typo: Case matters. documents and Documents are different
  2. Doesn't exist: First check with ls to confirm it exists
  3. Wrong location: Check where you are with pwd

Error 2: command not found

$ lss
bash: lss: command not found
Linny-senpai: This is a typo in the command name. The correct command is ls, not lss.

Error 3: Permission denied

$ cd /root
bash: cd: /root: Permission denied
Lina: What does this mean?
Linny-senpai: It means "you don't have permission." /root is an admin-only area, so regular users can't enter. We'll explain permissions in detail in another article.

Troubleshooting Steps

  1. Check where you are with pwd
  2. Check contents with ls
  3. Verify command spelling (watch for case sensitivity)
  4. View help with man command-name

Mini Exercises

Linny-senpai: Now let's do some mini exercises to confirm what you learned today!

Exercise 1: Check Your Location

Run pwd to check your current directory. Did you find out where you are?

Exercise 2: View File List

Run ls to see the files and folders in your current location. Then try ls -l for detailed view.

Exercise 3: Move Between Directories

Use cd to move to an existing directory, then verify with pwd. After that, return with cd ...

Lina: Done! If I check with ls before using cd, I can prevent errors.
Linny-senpai: Perfect! That's the basic flow of terminal operations.

Review

Lina: Today I learned the basics of the terminal. pwd for current location, ls for contents, and cd for moving!
Linny-senpai: Exactly! And when in trouble, Ctrl + C to cancel, and Tab for completion. With these basics down, you can keep learning more commands.
Lina: The black screen doesn't seem so scary anymore!
Linny-senpai: Wonderful! Next, let's learn commands for creating and deleting files!

3-Line Summary

  1. pwd for location, ls for contents, cd for moving - these 3 are the basics
  2. When in trouble: Ctrl + C to cancel, Tab for auto-completion
  3. When errors occur, start by checking with pwd and ls

Next Steps

Now that you understand the basics of the terminal, let's practice with actual commands!