Git Basics Guide

This guide covers the fundamental concepts, workflows, and essential commands you need to start using Git effectively.

1. Core Concepts

Understanding the basic terminology is the first step to mastering Git.

Repository (Repo): A directory where Git tracks all changes to your files. It contains the history of the project.
Commit: A saved snapshot of your project at a specific point in time. Every commit has a unique ID (hash) and a message describing the changes.
Branch: A movable pointer to a specific commit. It allows you to work on different features or fixes in isolation without affecting the main project.
HEAD: A special pointer that indicates the branch or commit you are currently looking at and working on.
Staging Area (Index): An intermediate holding area where you organize and format changes before officially committing them to the project history.

To understand how files move through Git, it helps to visualize the three main states a file can reside in:

Working Directory: Where you actively edit your files.
Staging Area: You use git add to move changes here, preparing them for a commit.
Local Repository: You use git commit to permanently store the staged changes in your local Git history.
Remote Repository: You use git push to upload your local commits to a remote server (like GitHub, GitLab, or Bitbucket) to share with others.

Here are the day-to-day commands you will use most often.

git init: Turns an existing local directory into a new Git repository.
git clone <url>: Downloads a copy of an existing remote repository to your local machine.

git status: Shows the state of your working directory and staging area (which files are modified, untracked, or staged).
git add <file>: Adds a specific file to the staging area. Use git add . to stage all modified files in the current directory.
git commit -m "Your message here": Takes everything in the staging area and saves it as a new commit with a descriptive message.

git push: Uploads your local branch commits to the remote repository.
git pull: Downloads new commits from the remote repository and automatically integrates them into your current local branch.

git log: Displays the chronological commit history for the current branch.

Branching is one of Git's most powerful features, allowing multiple people to work on a project simultaneously.

git branch: Lists all local branches. The current branch will have an asterisk (*) next to it.
git branch <branch-name>: Creates a new branch at the current commit.
git switch <branch-name> (or git checkout <branch-name>): Moves your HEAD pointer to the specified branch, updating your working directory to match.
git switch -c <branch-name>: A shortcut to create a new branch and switch to it immediately ( or git checkout -b <branch-name>).
git merge <branch-name>: Takes the commits from the specified branch and integrates them into the branch you are currently on.