Git

Git is a system that tracks changes to files over time. Think of it like a save button for every step of your work, but better — you can see exactly what changed, who changed it, and when.

When I write "everything is under version control" in my articles, I mean everything is tracked in Git 99% of the time. Every change to every file has a history. If something breaks, I can go back to an earlier version. If I want to try a new idea, I can create a separate branch without affecting the main project.

It is one of the most important tools in modern development. Without it, you would have to keep copies of files with names like "website-final-v3-really-final.zip" — and that is exactly what Git prevents.