Bash Working with Terminal

The terminal is the window where Bash commands are typed and executed. Before writing scripts, it is important to feel comfortable navigating the terminal. This topic covers the most essential commands every beginner must know.

What Is the Terminal?

The terminal is a text-based interface to the operating system. Everything that can be done with a mouse and GUI — opening folders, creating files, running programs — can also be done in the terminal using commands.

┌─────────────────────────────────────────┐
│           Terminal Window               │
│                                         │
│  user@machine:~$  _                     │
│                                         │
│  (Type a command here and press Enter)  │
└─────────────────────────────────────────┘

Understanding the Command Prompt

The command prompt is the text that appears before the cursor. It gives useful context at a glance.

user@hostname:~$
│    │         │  └─ $ means regular user  (# means root/admin)
│    │         └──── ~ means home directory
│    └──────────── hostname (machine name)
└───────────────── username

Navigating the File System

The Linux file system is like a tree. The root of the tree is /. Every folder and file lives somewhere inside that tree.

/
├── home/
│   └── john/
│       ├── documents/
│       └── scripts/
├── etc/
├── var/
└── usr/

pwd – Print Working Directory

This command shows the current location in the file system.

pwd

Output:

/home/john

ls – List Files and Folders

This command lists the contents of the current directory.

ls

Output:

documents  downloads  scripts

Common options for ls:

cd – Change Directory

This command moves from one folder to another.

cd documents

Move up one level (to the parent folder):

cd ..

Go directly to the home directory:

cd ~

Go to the root directory:

cd /

Creating Files and Folders

mkdir – Make Directory

This command creates a new folder.

mkdir myfolder

Create multiple nested folders at once with -p:

mkdir -p projects/bash/scripts

touch – Create an Empty File

touch notes.txt

nano – Create and Edit a File

Nano is a simple text editor inside the terminal.

nano notes.txt

┌─────────────────────────────────────────┐
│  Nano Editor                            │
│  Type your text here                    │
│                                         │
│  ^O = Save    ^X = Exit                 │
│  ^G = Help    ^K = Cut line             │
└─────────────────────────────────────────┘

Copying, Moving, and Deleting

cp – Copy Files

cp notes.txt backup.txt

Copy a folder and all its contents:

cp -r myfolder myfolder_backup

mv – Move or Rename Files

Move a file to another directory:

mv notes.txt documents/

Rename a file:

mv notes.txt mynotes.txt

rm – Remove Files

rm backup.txt

Remove a folder and everything inside it:

rm -rf myfolder

Warning: The rm -rf command permanently deletes files. There is no trash bin. Use it carefully.

Viewing File Contents

cat – Print File Content to Screen

cat notes.txt

less – View Large Files Page by Page

less largefile.txt

Press q to quit the less viewer.

head and tail – View Start or End of a File

head -5 notes.txt

tail -5 notes.txt

Finding Files

find – Search for Files

find /home/john -name "notes.txt"

which – Find the Location of a Command

which bash

Output:

/bin/bash

Getting Help for Any Command

Every Linux command has a built-in manual. Use man to read it.

man ls

Press q to quit the manual. For a quick summary, use --help:

ls --help

Terminal Shortcuts That Save Time

Absolute vs Relative Paths

Understanding paths is critical for navigating and writing scripts correctly.

┌────────────────────────────────────────────────┐
│  Absolute Path                                 │
│  Starts from root /                            │
│  Example: /home/john/documents/notes.txt       │
│  Works from anywhere in the file system        │
├────────────────────────────────────────────────┤
│  Relative Path                                 │
│  Starts from the current directory             │
│  Example: documents/notes.txt                  │
│  Works only when in /home/john                 │
└────────────────────────────────────────────────┘

Key Takeaways

• Use pwd to see current location and cd to move between folders.
• Use ls to list contents, mkdir to create folders, and touch to create files.
• Use cp, mv, and rm to manage files.
• Use cat, less, head, and tail to read file content.
• The Tab key auto-completes commands and file names — use it constantly.