What is Git?

Git is a tool that remembers every version of your project, so you never lose work and can always see who changed what, and why.

Think of a college group assignment. Five friends are writing one report. Without a system, you email report_final.doc, then report_final_v2.doc, then report_FINAL_really.doc, and nobody knows which one is the latest. Two people edit the same page and one person's work is lost.

Git solves exactly this problem — for code, and for any files that change over time.

What Git actually does

Git keeps a history of your project. Every time you finish a piece of work, you take a snapshot (called a commit). Git stores that snapshot forever. Later you can:

• See the project exactly as it was last Tuesday.
• Find out who changed a line, and read the message they left explaining why.
• Let five people work on the same project at once, then combine everyone's changes safely.
• Try a risky idea on the side without touching the working version.

Why it matters

Almost every software company in the world runs on Git — from a two-person startup in Pune to Google. If you are a student or a new engineer, Git is not optional; it is the first tool you pick up on any real team.

The good news: the ideas are simple. You only need a handful of them to be productive.

The words you'll keep hearing

You do not need to understand these fully yet — each has its own page in this guide. Just get a feel for them:

• Repository (repo) — the project folder that Git is tracking.
• Commit — one saved snapshot, with a short message.
• Branch — a separate line of work, so you don't disturb the main version.
• Push / Pull — send your commits to a shared server / bring others' commits down.
• Pull request (PR) — asking for your changes to be reviewed and added to the main project.
• Merge — combining two lines of work into one.

Git vs GitHub, GitLab, Sangam-Git

People mix these up. Here is the difference:

• Git is the tool that runs on your computer and does the actual version tracking.
• Sangam-Git (like GitHub or GitLab) is a website where teams store their Git projects together, review each other's work, and collaborate.

You use Git on your laptop; you use Sangam-Git in your browser and to share code with your team. The next pages explain each idea, one at a time.

Try it: Git is already installed on most Macs and Linux machines. Open a terminal and type git --version. If you see a version number, you're ready.