Git Beginners Guide | Install· Commit

What is Git?

Git is the world’s most widely used version control system (VCS) — a tool that tracks every change to your files, lets you revert to any previous state, and enables many people to collaborate on the same codebase.

Without Git:          With Git:
project_v1.zip        git log → full history
project_v2.zip        git checkout → any version
project_FINAL.zip     git branch → parallel work
project_FINAL2.zip    git merge → combine work

This guide covers the core workflow. By the end you will be able to:

1. Install and configure Git
2. Stage and commit changes
3. Create and switch branches
4. Push to and pull from GitHub

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Installation

macOS

# Option 1: Homebrew (recommended)
brew install git

# Option 2: Xcode Command Line Tools
xcode-select --install

Windows

Download the installer from git-scm.com and follow the wizard. Use Git Bash for all commands in this guide.

Linux (Ubuntu / Debian)

sudo apt update && sudo apt install git

Verify

git --version
# git version 2.44.0

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Initial Configuration

Run these once after installation:

Run these Git commands:

git config --global user.name "Your Name"
git config --global user.email "you@example.com"

# Set default branch name to 'main'
git config --global init.defaultBranch main

# Use VS Code as the default editor
git config --global core.editor "code --wait"

# Better diff output
git config --global core.autocrlf input    # macOS/Linux
# git config --global core.autocrlf true   # Windows

Check your settings:

git config --list

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Core Concepts

Working Directory  →  Staging Area  →  Repository
    (your files)       (git add)       (git commit)
                                            ↓
                                      Remote (git push)

Term	What it is
Repository (repo)	The .git folder that stores all history
Working directory	The files you see and edit
Staging area (index)	A “draft” of your next commit
Commit	A snapshot of your staged changes with a message
Branch	A movable pointer to a sequence of commits
Remote	A copy of the repo on another machine (e.g. GitHub)

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Basic Workflow

1. Initialize a Repository

mkdir my-project && cd my-project
git init
# → Initialized empty Git repository in .../my-project/.git/

Or clone an existing repo:

git clone https://github.com/user/repo.git
cd repo

2. Check Status

git status

Always run git status before staging or committing — it shows:

• Untracked files (new files Git doesn’t know about yet)
• Modified files (changed since last commit)
• Staged files (ready to commit)

3. Stage Changes

Run the following commands:

# Stage a specific file
git add README.md

# Stage multiple files
git add src/main.py tests/test_main.py

# Stage all changes in the current directory
git add .

# Interactive staging (choose hunks)
git add -p

4. Commit

git commit -m "Add README with project overview"

Good commit message formula:

<type>: <short summary> (50 chars max)

<optional body — explain WHY, not what>

Types: feat, fix, docs, refactor, test, chore

# Examples
git commit -m "feat: add user registration endpoint"
git commit -m "fix: prevent duplicate email on signup"
git commit -m "docs: update API authentication section"

5. View History

Run the following commands:

# Full log
git log

# One line per commit
git log --oneline

# With graph (useful for branches)
git log --oneline --graph --all

# Show changes in last 3 commits
git log -p -3

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Branching

Branches let you work on features or fixes without touching the main codebase.

Run the following commands:

# Create and switch to a new branch
git checkout -b feat/user-profile

# Modern syntax (Git 2.23+)
git switch -c feat/user-profile

# List all branches
git branch -a

# Switch to an existing branch
git switch main

# Delete a merged branch
git branch -d feat/user-profile

# Force delete (even if unmerged)
git branch -D feat/user-profile

Typical Feature Branch Workflow

Run the following commands:

# 1. Start from an up-to-date main
git switch main
git pull

# 2. Create a feature branch
git switch -c feat/42-add-search

# 3. Make changes and commit
git add src/search.py
git commit -m "feat: add full-text search with SQLite FTS5"

# 4. Merge back into main
git switch main
git merge feat/42-add-search

# 5. Clean up
git branch -d feat/42-add-search

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Merging & Resolving Conflicts

git merge feat/42-add-search

If Git can merge automatically, it creates a merge commit. If two branches changed the same lines, you get a conflict:

<<<<<<< HEAD (main)
def search(query):
    return []
=======
def search(query, limit=10):
    return db.query(query, limit)
>>>>>>> feat/42-add-search

To resolve:

1. Edit the file — keep what you want, delete the markers
2. git add <file>
3. git commit

VS Code makes this easier

Open the conflicted file in VS Code and use the “Accept Current / Accept Incoming / Accept Both” buttons in the diff view.

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Undoing Changes

Run the following commands:

# Unstage a file (keep changes in working directory)
git restore --staged README.md

# Discard changes in working directory (IRREVERSIBLE)
git restore README.md

# Undo the last commit, keep changes staged
git reset --soft HEAD~1

# Undo the last commit, keep changes in working directory
git reset --mixed HEAD~1

# Create a new commit that reverses a previous commit (safe for shared branches)
git revert HEAD

# Show what changed in the last commit
git show HEAD

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Remote Repositories (GitHub)

Push an Existing Repo to GitHub

Run the following commands:

# 1. Create a repo on github.com (no README, no .gitignore)

# 2. Connect your local repo
git remote add origin https://github.com/you/my-project.git

# 3. Push and set upstream
git push -u origin main

# After the first push, just:
git push

Pull Updates

Run the following commands:

# Fetch + merge in one step
git pull

# Fetch only (inspect before merging)
git fetch
git log origin/main  # see what's new
git merge origin/main

.gitignore

Create a .gitignore file at your repo root to exclude files from tracking:

Run the following commands:

# Python
__pycache__/
*.pyc
.env
venv/
.venv/

# Node
node_modules/
dist/
.next/

# Editors
.DS_Store
.idea/
.vscode/settings.json

# Build artifacts
*.log
*.tmp

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Common Troubleshooting

I committed to the wrong branch

# Move last commit to a new branch
git branch feat/new-branch   # create branch pointing at current commit
git reset --hard HEAD~1      # remove commit from current branch
git switch feat/new-branch   # go to the new branch

I want to change the last commit message

git commit --amend -m "New message"
# ⚠️ Only do this if you haven't pushed yet

I accidentally deleted a file

git checkout HEAD -- deleted-file.txt

I need to temporarily set aside work

Run the following commands:

# Stash uncommitted changes
git stash

# Get them back
git stash pop

# List stashes
git stash list

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Essential Command Reference

Command	What it does
git init	Initialize a new repository
git clone <url>	Clone a remote repository
git status	Show working tree status
git add <file>	Stage a file
git commit -m "msg"	Create a commit
git log --oneline	Show compact commit history
git branch -b <name>	Create + switch to branch
git merge <branch>	Merge a branch into current
git push	Push to remote
git pull	Pull from remote
git stash	Temporarily shelve changes
git revert HEAD	Safely undo last commit

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Next Steps

• Branching strategies: Learn Git Flow or GitHub Flow for team collaboration
• Rebase: git rebase for a cleaner history
• GitHub Actions: Automate CI/CD on push or pull request

Related posts:

• GitHub Actions CI/CD Guide
• Cursor AI Editor Guide

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Frequently Asked Questions (FAQ)

Q. When would I use this in practice?

A. Git basics from scratch. Learn how to install Git, stage and commit changes, create branches, resolve merge conflicts.

Q. What should I read before this?

A. Follow the previous article or related articles links at the bottom of each post to learn in sequence.

Q. Where can I study this more deeply?

A. Check cppreference and the relevant library’s official documentation. The reference links at the end of the article are also worth using.

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Related Articles (Internal Links)

Other articles related to this topic.

• GitHub Actions 완벽 가이드 | CI/CD·자동화·Workflow·배포·실전 활용
• Cursor AI 에디터 완전 가이드 | VS Code 기반 AI 코딩 도구 실전 활용

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Keywords Covered in This Article (Related Search Terms)

This article covers Git, Version Control, GitHub, Collaboration, Beginner Guide.