Basic Linux Commands

The Terminal

The terminal (or shell) is where you type commands to interact with Linux. Think of it as a text-based control center that lets you navigate files, manage processes, install software, and much more. The default shell on most Linux distributions is Bash (Bourne Again SHell).

Navigation Commands

pwd — Print Working Directory

Shows the full path of your current location in the file system.

$ pwd

ls — List Files

Displays the contents of a directory. Add flags for more detail.

$ ls
$ ls -la
$ ls -lh /var/log

cd — Change Directory

Navigates to a different directory. Use special shortcuts to move quickly.

$ cd /home/user/Documents
$ cd ..        # Go up one directory
$ cd ~         # Go to home directory
$ cd -         # Go to previous directory

File Operations

mkdir — Make Directory

Creates new directories. Use the -p flag to create nested directories in one go.

$ mkdir projects
$ mkdir -p projects/web/css    # Create nested directories

touch — Create Files

Creates empty files or updates the timestamp of existing files.

$ touch hello.txt
$ touch file1.txt file2.txt file3.txt

cp — Copy Files

Copies files or directories. Use -r to copy directories recursively.

$ cp file.txt backup.txt           # Copy file
$ cp -r projects/ backup/          # Copy directory

mv — Move / Rename Files

Moves files to a new location, or renames them if the destination is in the same directory.

$ mv old.txt new.txt               # Rename
$ mv file.txt /home/user/Documents/ # Move

rm — Remove Files

Deletes files and directories. Be careful — removed files don't go to a trash can!

$ rm file.txt                      # Remove file
$ rm -r directory/                 # Remove directory
$ rm -rf directory/                # Force remove (use with caution!)

Viewing File Content

cat — Display File Content

Outputs the entire content of a file to the terminal.

$ cat hello.txt

head / tail — View Beginning / End of Files

Peek at the first or last lines of a file — perfect for large log files.

$ head -n 5 log.txt    # First 5 lines
$ tail -n 10 log.txt   # Last 10 lines
$ tail -f log.txt      # Follow (live updates)

grep — Search Inside Files

Finds lines matching a pattern inside one or more files.

$ grep "error" log.txt
$ grep -i "warning" log.txt    # Case insensitive
$ grep -r "TODO" ./src/        # Recursive search

System Information

Quick reference for commands that tell you about your system.

# Step 1: Where am I?
$ pwd
/home/user

# Step 2: What's in this directory?
$ ls -la

# Step 3: Create a practice directory
$ mkdir linux-practice

# Step 4: Go inside and create a file
$ cd linux-practice
$ echo "My first Linux note!" > notes.txt

# Step 5: Read the file
$ cat notes.txt
My first Linux note!

Command Cheat Sheet

A quick-reference table of the most common commands grouped by category.