Version control with GitHub Desktop
This is the lesson that saves your afternoon. You have a working resource from Module 02. One careless edit, one corrupted file, one "I'll just try this", and it's gone. Git is the safety net. The mental model is trivial: git takes snapshots of your folder, and each snapshot is called a commit. GitHub Desktop is the button-based way to start using git right now, no terminal required.
Build it
Install GitHub Desktop and sign in
Go to desktop.github.com and download the installer for your operating system (Windows or macOS). Run it and accept the defaults.
On first launch it asks you to sign in. Click , authorise in the browser tab that opens, then return to the app. When it asks for your name and email, use anything you like; these become the author shown on your commits.