Understanding Git Architecture

Git operates as a distributed version control system, where each developer maintains a complete local repository containing all branches and commit history. This differs from centralized systems that rely on a single server.

Core Git concepts include:

• Distributed Model: Every contributor possesses a full repository copy
• Data Integrity: SHA-1 hashing ensures content protection
• Efficient Networking: Only differential data transfers during operations
• Branch Management: Lightweight branching enables isolated development
• Staging Area: Selective commit preparation through indexed changes

Local Repository Operations

Initial Configuration

Before using Git, configure user identity:

git config --global user.name "developer-name"
git config --global user.email "developer@domain.com"

Verify configuration:

git config --list

Repository Initialization

Create a working directory and initialize Git tracking:

mkdir project-folder
cd project-folder
git init

This creates a hidden .git directory containing repository metadata.

Version Creation Workflow

Modify files in the working directory, then stage and commit changes:

# Stage all modifications
git add .

# Stage specific file types
git add *.js

# Stage individual files  
git add script.js

# Commit staged changes with message
git commit -m "Initial feature implementation"

Version Navigation

View commit history:

git log --oneline

Navigate between versions:

# Return to previous commit
git reset --hard HEAD^

# Go back two commits
git reset --hard HEAD^^

# Navigate 5 commits back
git reset --hard HEAD~5

# Switch to specific commit using hash
git reset --hard a1b2c3d

File Recovery Scenarios

Scenario 1: Unstaged modifications

git checkout -- filename.txt

Scenario 2: Staged but uncommitted changes

git reset HEAD filename.txt
git checkout -- filename.txt

Sceanrio 3: Committed changes - use version navigation

Scenario 4: File deletion

# Restore deleted file
git checkout -- deleted-file.txt

# Permanent removal from repository
git rm permanent-delete.txt
git commit -m "Remove obsolete file"

Branch Management

Branch Operations

Create and manage development branches:

# List existing branches
git branch -a

# Create new branch
git branch feature-branch

# Switch to branch
git checkout feature-branch

# Create and switch simultaneously
git checkout -b new-feature

# Merge branch into current
git merge source-branch

# Delete merged branch
git branch -d completed-branch

# Force delete unmerged branch
git branch -D abandoned-branch

Merge Conflict Resolution

When branches contain conflicting changes:

1. Git halts merge operation
2. Conflict markers appear in affected files
3. Manually resolve conflicts by editing files
4. Stage resolved files and complete merge:

git add resolved-file.js
git commit -m "Merge conflict resolution"

Remote Repository Integration

SSH Authentication Setup

Generate SSH keys for secure remote access:

ssh-keygen -t rsa -C "developer@company.com"

Copy public key to remote service:

cat ~/.ssh/id_rsa.pub

Remote Reposiotry Connection

Link local repository to remote:

git remote add origin git@host.com:user/repository.git

Synchronize local repository with remote:

git pull origin main --allow-unrelated-histories

Push local commits to remote:

git push origin main

Essential Command Reference

• git status: Check repository state
• git diff: View unstaged changes
• git log: Examine commit history
• git clone: Copy remote repository
• git fetch: Download remote changes
• git stash: Temporarily store modifications