Lesson 01 — What Git and GitHub Are

Goal

Understand what Git and GitHub do, and why teams use them.

Plain-language explanation

Git is a tool on your computer that tracks changes to files over time.

GitHub is a website where Git repositories can be stored, shared, reviewed, and discussed.

A repository, often called a repo, is a project folder that Git is tracking.

Why this matters for data work

Git helps teams answer questions like:

• What changed in this analysis script?
• Who made the change?
• When did it change?
• Why did it change?
• Can we review a change before it becomes official?
• Can we go back to an earlier version if needed?

Core mental model

Your computer = local repository
GitHub = remote repository

You make changes locally, save them in Git, then send them to GitHub.

Checklist

• I can explain that Git tracks file changes.
• I can explain that GitHub hosts repositories online.
• I can explain that a repository is a project folder tracked by Git.
• I understand that my computer and GitHub can each have a copy of the repo.
• I understand that Git is useful for collaboration and review.

Key words

• Repository: A project folder tracked by Git
• Local: On your computer
• Remote: On GitHub or another server
• Commit: A saved checkpoint in Git history
• Branch: A separate workspace for a change
• Pull request: A request to review and merge a branch

Reflection prompt

Think of one file you work on regularly. What would be useful about knowing exactly what changed in that file over time?