Path 8 · Command line
Linux and Command-Line Skills
Use the Linux terminal with safe, explained commands, understand users, permissions and processes, and meet the Windows command line.
By the end you will be able to
- Explain the terminal, shell and prompt.
- Navigate and manage files with safe Linux commands.
- Read permissions and system information.
- Compare Linux and Windows command-line tools.
Before you start
- Recommended first: Files, Storage and Digital Organisation
- Recommended first: Operating System Mastery
Module 29: Understanding the terminal
What the terminal and the shell are, how to read a prompt and a command, and the everyday habits (paths, quoting, history, tab completion and Ctrl+C) that make typing commands safe and fast.
- Terminal, shell and your first commands
Learn what the terminal and the shell are, how to open the terminal on Ubuntu, and how to read a prompt, a command and its output. You will run your first harmless commands.
25 min · beginner · Ubuntu/Linux
- Paths, case sensitivity, quoting, history and tab completion
Learn where the terminal thinks you are, how absolute and relative paths differ, why capital letters and spaces matter, and four habits that save typing: history, tab completion, quotes and Ctrl+C.
25 min · beginner · Ubuntu/Linux
Module 30: Safe Linux commands
Find your way around the Linux file system, create and copy files in a practice folder, read and search text, check on your computer's health, and meet permissions, help pages, sudo and apt with the right warnings.
- Finding your way: pwd, ls and cd
Learn three commands that only look and move: pwd shows where you are, ls shows what is there and cd takes you somewhere else. You also make a practice folder so every later exercise is safe.
25 min · beginner · Ubuntu/Linux
- Making, copying and moving: mkdir, touch, cp and mv
Create folders and empty files, copy them, move them and rename them, always inside ~/practice. You also learn how a copy or move can silently overwrite a file, and meet rm as a clearly flagged danger.
30 min · beginner · Ubuntu/Linux
- Reading and searching: file, cat, less, head, tail, grep and find
Look inside files without changing them, search their text with grep, find files by name with find, and join commands together with a pipe. Every command here only reads.
30 min · elementary · Ubuntu/Linux
- Looking at the system: df, du, free, ps, top, whoami and id
Use seven read-only commands to see how full your disk is, how much memory is in use, which programs are running and which account you are using, and learn to read each result.
25 min · elementary · Ubuntu/Linux
- Permissions, getting help, sudo and packages
Read the permission string from ls -l, change a practice file's permissions with chmod, find help with man and --help, and meet sudo and apt with the right caution, including why you should never paste a command you do not understand.
30 min · intermediate · Ubuntu/Linux
Module 31: Linux system concepts
How Linux decides who may do what, how programs and services run and leave logs, and how the filesystem, environment variables and a first safe shell script fit together.
- Users, groups and permissions in depth
Understand how Linux knows who you are, what a group is, how to read the permission string from `ls -l` and how to change permissions safely on your own practice files.
30 min · elementary · Ubuntu/Linux
- Processes, services, packages and logs
Learn how Linux runs programs as processes, how background services are managed, where software comes from and how to read the logs that explain what went wrong.
30 min · elementary · Ubuntu/Linux
- The filesystem hierarchy, environment variables and shell scripts
Learn where Linux keeps its own files and yours, how to check disk space, what environment variables and PATH are, and how to write and run a first safe shell script in your practice folder.
30 min · elementary · Ubuntu/Linux
Module 32: Windows command-line fundamentals
How Command Prompt, PowerShell and Windows Terminal differ, and how to move around, manage files, inspect processes and test the network on Windows with safe, practice-folder examples.
- Command Prompt and PowerShell
Learn the difference between Command Prompt, PowerShell and Windows Terminal, open them on Windows 11, move around folders, list files and create a practice folder, with a table comparing PowerShell and Linux commands.
25 min · beginner · Windows
- Files, processes and network diagnostics on Windows
Copy and move files inside a practice folder, list running processes, read ipconfig and ping results, find help with Get-Help and /?, and understand why running as administrator needs caution.
30 min · elementary · Windows