What is a commit?

New idea

Which file is the final one?

Saving a copy every time you change something feels safe, until the folder holds essay.docx, essay_final.docx and essay_final_v2_REAL.docx. Which one is the latest? What changed between them? Nobody remembers.

Now picture 5 people on one project, emailing files back and forth. Two of them fix the same file on the same day, and one fix quietly overwrites the other.

Version control solves this. A tool like Git remembers every saved version of the whole project, who made it and why. You can go back to any version, and a whole team can work at once without losing each other's work.