✏️ Lesson 4.2: Text Editors: nano and vim

Why Edit in the Terminal?

You might wonder why you'd edit text in a terminal when GUI editors like VS Code exist. Here's why terminal editors matter:

• Remote servers — when you SSH into a server, the terminal is all you have
• System configuration — many config files need to be edited as root with sudo
• Quick edits — sometimes it's faster than opening a GUI application
• Everywhere — nano and vim are installed on virtually every Linux system

nano — The Friendly Editor

nano works like any text editor you've used: type text, use keyboard shortcuts to save and quit. No modes, no surprises.

# Open a file (creates it if it doesn't exist)
nano myfile.txt

# Open a file at a specific line number
nano +15 myfile.txt

# Open a file as root (for system configs)
sudo nano /etc/hosts

  GNU nano 7.2          myfile.txt

Hello, this is my file.
I can just type here like normal.
│  ← cursor

^G Help    ^O Write Out  ^W Where Is   ^K Cut
^X Exit    ^R Read File  ^\ Replace    ^U Paste

Essential nano Shortcuts

nano Beyond the Basics

Selecting and Copying Text

# Start a selection (set mark)
Alt+A  (then move cursor to highlight)

# Copy the selection
Alt+6

# Cut the selection
Ctrl+K

# Paste
Ctrl+U

Useful Startup Options

# Open with line numbers displayed
nano -l myfile.txt

# Open with soft line wrapping
nano -$ myfile.txt

# Open in read-only mode
nano -v myfile.txt

# Open with syntax highlighting (auto-detected by extension)
nano script.sh  # automatically highlights bash syntax

Customizing nano with .nanorc

# Create or edit your nano config
nano ~/.nanorc

# Add these useful settings:
set linenumbers      # Always show line numbers
set tabsize 4        # 4-space tabs
set autoindent       # Auto-indent new lines
set mouse            # Enable mouse support
set softwrap         # Wrap long lines visually

vim — The Powerful Editor

vim (Vi IMproved) is a modal editor — it has different modes for different tasks. This feels alien at first, but once it clicks, many developers find it faster than any other editor.

# Open a file
vim myfile.txt

# Open at a specific line
vim +15 myfile.txt

# Open as root
sudo vim /etc/hosts

# If vim isn't installed, install it:
sudo apt install vim

vim Modes

vim's key concept: different modes for different actions. This is what makes it confusing at first — and powerful once you understand it.

vim Essentials

Entering Insert Mode

Navigation (Normal Mode)

Editing (Normal Mode)

Saving and Quitting (Command Mode)

Search and Replace in vim

Searching

# Search forward (from Normal mode)
/search_term     # then press Enter

# Search backward
?search_term

# Next match
n

# Previous match
N

# Turn off search highlighting
:noh

Search and Replace

# Replace first occurrence on current line
:s/old/new/

# Replace ALL occurrences on current line
:s/old/new/g

# Replace all occurrences in the ENTIRE file
:%s/old/new/g

# Replace with confirmation (y/n for each)
:%s/old/new/gc

# Case-insensitive replace
:%s/old/new/gi

Choosing an Editor

Setting Your Default Editor

# Set nano as the default editor for git, crontab, etc.
export EDITOR=nano
export VISUAL=nano

# Make it permanent — add those lines to:
nano ~/.bashrc

# Or set vim:
export EDITOR=vim
export VISUAL=vim

Exercises

# Create a test file
echo -e "Hello World\nHello Linux\nHello Terminal" > hello.txt

# Open in nano
nano hello.txt

# Press Ctrl+\ to search and replace
# Search: Hello
# Replace: Goodbye
# Press A to replace all

# Save and exit: Ctrl+O, Enter, Ctrl+X

# Create a test file and open it
echo -e "Line one\nLine two\nLine three\nLine four\nLine five" > vimtest.txt
vim vimtest.txt

vim hello.txt
# In Normal mode, type:
# :%s/Goodbye/Hey/g
# Press Enter
# All "Goodbye" replaced with "Hey"
# :wq to save and quit

# Clean up
rm practice.txt hello.txt practice_vim.txt vimtest.txt

Knowledge Check

Quick Reference

nano Cheat Sheet

vim Cheat Sheet

Summary

🚀 What's Next?

Module 5 dives into package management — installing, updating, and removing software with apt, Snap, Flatpak, and more.