---
title: "Intro to git"
sub_title: "git push -f origin main"
author: "Prabuddha Hans"
date: "2025-09-22"

theme:
    name: catppuccin-latte
---

# Git

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Git is tool that's used in the programming industry.

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Another name for Git is a Version Control System (VCS) tool.

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Specifically to track project work done, and the changes to files we've made.

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The more correct term is Source Control.

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It is NOT a programming language.

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Git is a tool made for (usually) us programmers to track the work we've done.

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Programmer socks (not) included.

![image:width:100%](intro_to_git/compsocks.png)

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Now we need to ask WHY.


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Why would we need a tool like this?

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Why not use Google Drive instead?

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I will find your IP address.

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In all honesty,

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It's to help keep track of who did what.

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And to work on unique features...

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without affecting the main area/branch of our work.

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When DO we use git?

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Because Git keeps track of the changes we've made to files,

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We can then use it to commit and stage these files,

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and push them to a place where we can store them.

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This place is called a Repository.

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Repositories are hosted on websites like GitLab, GitHub and Forgejo.

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But, an interesting feature of git, is that it allows you to time-travel.

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Meaning that if a project breaks, you can go back to before it broke.

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Now I hear you in the audience asking...

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Why not use SVN?

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The answer is simple.

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![image:width:100%](intro_to_git/NAH.jpg)

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An actual answer is that Git is Distributed, and SVN in centralized.

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Simply put, devs can store their changes locally on their machines,

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where on SVN they're stored on a central system.

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With a central system you NEED to be connected at all times to work on it.

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You can work locally on git without having to be connected,

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and then push once you're reconnected.

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Back to git.

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Let's start with the basics.

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# Live demonstration time

Please get your laptops out

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How to download Git & Git LFS

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## Download
<<https://git-scm.com/downloads>>

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![image:width:100%](intro_to_git/git_download_button.png)

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![image:width:100%](intro_to_git/git_installer.png)

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![image:width:100%](intro_to_git/git_installer_notepad_as_default_editor.png)

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![image:width:100%](intro_to_git/git_installer_rename_master_to_main.png)

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![image:width:100%](intro_to_git/git_installer_checkout_unix.png)

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![image:width:100%](intro_to_git/git_installer_default_rebase_pull.png)

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<<https://forgejo.skynet.ie/Skynet/deploy_user>>

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Don't do this
![image:width:100%](intro_to_git/bad_message.png)

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![image:width:100%](intro_to_git/forgejo_template_button.png)

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![image:width:100%](intro_to_git/forgejo_template_repo_creation.png)

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![image:width:100%](intro_to_git/forgejo_repo_link.png)

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LFS Install

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````bash 
git lfs install
````

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Setup SSH key (see Readme.md))

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![image:width:100%](intro_to_git/forgejo_repo_settings.png)

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![image:width:100%](intro_to_git/forgejo_secrets_location.png)

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![image:width:100%](intro_to_git/forgejo_add_secret.png)

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![image:width:100%](intro_to_git/forgejo_ssh_key_example.png)

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````bash
git init
git remote add origin <repo_url>
git pull origin <branch_name>
git add <file_name>
git commit -m "<commit_message>"
git push origin <branch_name>
````

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``https://<username>.users.skynet.ie/``

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TroubleShooting

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If you see this:

![image:width:100%](intro_to_git/permission_denied_publickey.jpg)

> Credit: Geeks for Geeks

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Go here: https://docs.github.com/en/authentication/connecting-to-github-with-ssh/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent

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