A comprehensive Git and GitHub crash course

What is Git?

Git is a widely-used version control system that allows software developers to track changes to their source code over time. It provides tools for collaboration, managing different versions of code, and easily reverting to previous versions if necessary.

What is Github?

GitHub is a web-based platform that provides developers with a centralized location to store and manage their Git repositories, collaborate with others on code, and host and review code. It also offers project management tools and features such as issue tracking, wikis, and code reviews.

Git Installation

To install Git on your computer, you can follow these general steps:

1. Go to the Git website:?https://git-scm.com/
2. Click on the “Download” button, which will take you to the downloads page.
3. Select the appropriate installer for your operating system (e.g., Windows, Mac, Linux).
4. Run the installer and follow the on-screen instructions to complete the installation.
5. Once the installation is complete, you can verify that Git is installed correctly by opening a terminal or command prompt and typing “git — version”. If Git is installed correctly, you should see the version number displayed.

Note that the exact steps for installing Git may vary slightly depending on your operating system and the version of Git you are installing. The Git website provides detailed installation instructions for each operating system, which you can follow to ensure that Git is installed correctly.

Git Setup

Run these commands and your git will be ready to use the useful commands.

git config --global user.name "John Doe" # your name
git config --global user.email [email protected] # your email        

Essential Git commands

Git init

git init?is a command used to initialize a new Git repository in a directory. It creates an empty repository with the necessary files and folders to track changes, enabling version control for the project.

$ git init
Initialized empty Git repository in /path/to/your/directory/.git/        

Git add

git add?is a command used in Git to add changes made to files to the staging area, preparing them to be committed. It allows you to select specific files or directories to track for changes and include in the next commit.

git add . # to add all files
git add filename # add a specific file        

Git status

Git status is a command used in Git version control system to display the current state of the repository. It shows information about any modified, added, or deleted files, as well as untracked files. For example:

$ git status
On branch master
Your branch is up to date with 'origin/master'.        

Git commit

A git commit is a snapshot of your code changes that you save in the version control system. It represents a milestone in the project’s history and includes a unique identifier, a message describing the changes, and references to the modified files.

$ git commit -m "Add feature X to the project"        

Git push

git push?is a command used in Git to upload the local changes of a branch to a remote repository. It updates the remote repository with the latest commits, allowing collaboration and synchronization between team members.

$ git push origin master        

Git clone

git clone?is a command used to create a local copy of a remote Git repository. It downloads all the files and history from the remote repository and sets up a local copy on your machine, allowing you to work with the code and contribute changes.

git clone https://github.com/example/repository.git        

Git branch

A Git branch is a pointer to a specific commit in a repository’s version history. It allows for the creation and isolation of independent lines of development. An example would be creating a new branch called “feature-branch” from the “master” branch using the command:

Create a branch

$ git branch branchname        

Check all branches

$ git branch        

Switch branches

$ git checkout branchname        

Merge a branch

$ git merge branchname        

How to connect a repository to Github

To connect a GitHub repository to your local machine, you can follow these steps:

1. Create a new repository on GitHub.
2. On your local machine, navigate to the directory where you want to store your project.
3. Initialize a new Git repository in that directory using the command:

$ git init        

4. Add your GitHub repository as a remote to your local repository by running:

$ git remote add origin <repository-url>        

Replace?<repository-url>?with the URL of your GitHub repository. This establishes a connection between your local repository and the remote repository on GitHub.

5. Verify the remote connection by running:

$ git remote -v        

This command will display the configured remotes, and you should see the origin URL.

6. You can now push your local repository to GitHub by running:

$ git push -u origin master        

This command pushes the master branch of your local repository to the origin remote on GitHub. After this initial push, you can use?git push?to send subsequent changes to GitHub.

Congrats! Your local repository is now connected to the GitHub repository, allowing you to easily push and pull changes between the two.