Text editors: nano & vim basics

Sooner or later every Linux user has to edit a file in the terminal: a config file on a server, a crontab, a commit message, a script. There's no mouse-driven GUI on a server, so you need a terminal text editor. You'll learn two: nano, which is simple and beginner-friendly, and vim, which is powerful, everywhere, and well worth knowing the basics of.

nano: the friendly editor#

nano notes.txt              # open (or create) a file
nano -l /etc/hosts          # show line numbers
sudo nano /etc/ssh/sshd_config   # system files need sudo

nano works like a normal editor: just start typing. The bottom two lines list the shortcuts, where ^ means Ctrl and M- means Alt:

That's genuinely all you need to edit config files. A good habit before editing system files is to keep a backup copy:

sudo cp /etc/ssh/sshd_config /etc/ssh/sshd_config.bak
sudo nano /etc/ssh/sshd_config

vim: the editor that's everywhere#

vi (and its improved version vim, or the modern fork neovim) is installed on virtually every Unix-like system, including minimal servers and containers where nano might be missing. Many tools (git commit, crontab -e, visudo) may open it by default. Knowing the basics means you'll never be stuck.

vim notes.txt

The key idea: modes

vim is a modal editor. Keys do different things depending on the mode:

If you're ever confused, press Esc (twice is fine) to get back to normal mode.

Survival kit

Your first edit, step by step: vim hello.txt → press i → type Hello from vim → press Esc → type :wq → Enter. Done.

Moving around

Editing in normal mode

These are vim's superpower. Commands combine a verb with a motion and an optional count:

So d3w deletes three words and y$ copies to the end of the line. Once the grammar clicks, editing gets very fast.

Search and replace

/timeout          search forward for "timeout"; n = next, N = previous
?timeout          search backward
:%s/http/https/g  replace every "http" with "https" in the whole file
:%s/old/new/gc    the same, but confirm each replacement
:10,20s/^/# /     comment out lines 10–20 by adding "# " at the start

Handy settings

Type these in command-line mode, or put them (without the :) in ~/.vimrc to make them permanent:

:set number         show line numbers
:set paste          paste text without auto-indent mangling it (:set nopaste afterwards)
:syntax on          syntax highlighting
:set ignorecase smartcase   case-insensitive search unless you type capitals

To learn properly, run vimtutor: a 30-minute interactive lesson built into vim.

Choosing your default editor#

Commands like crontab -e, git commit and sudoedit open the editor named in the EDITOR (or VISUAL) environment variable:

export EDITOR=nano                   # for this session
echo 'export EDITOR=nano' >> ~/.bashrc   # permanently

On Debian/Ubuntu, sudo update-alternatives --config editor sets the system default, and select-editor sets your own default for some tools.

Editing system files safely#

• sudoedit /etc/file (or sudo -e) copies the file to a temporary location, opens your editor as your user, and writes it back as root when you save. It's safer than running a whole editor as root.
• visudo for /etc/sudoers and crontab -e for cron jobs check your syntax before saving. Always use them instead of editing those files directly.
• Validate before restarting services: sudo nginx -t, sudo sshd -t, sudo apachectl configtest. A typo in sshd_config can lock you out of a server.

Other editors#

• micro: a modern terminal editor with familiar Ctrl+S / Ctrl+C / Ctrl+V keys (sudo apt install micro).
• emacs: the other legendary editor, endlessly extensible.
• VS Code Remote-SSH: edit files on a server from your desktop editor. It's great for development, but you'll still want nano or vim for quick fixes.

Common mistakes#

• Getting stuck in vim. Press Esc, then type :q! and Enter to quit without saving, or :wq to save and quit.
• Typing commands in Insert mode in vim, so :wq ends up as text in the file. Press Esc first.
• Editing system files without sudo, then being unable to save. Use sudo nano /etc/file, or better, sudoedit /etc/file.
• Breaking a config file and restarting the service blindly. Make a backup copy first (sudo cp file file.bak) and use the program's config test (e.g. sudo nginx -t).

What's next#

You can now read and edit any file. Next: who's allowed to read and edit them, with permissions and ownership.