What is GIT and GitHub | The Ultimate Difference

git-vs-github

Many people who have just started to work in a collaborative environment encounter with the term Git and most of the time they are not able to differentiate between Git and GitHub. Here in this post we learn about Git and GitHub and see how are they related to each other. Also, Git was created by Linus Torvalds (the mastermind behind Linux) and is written in C#.

git-vs-github

First, we will understand what is GIT :

Git is a piece of software which increases our efficiency while writing the code. Git is a Version Control System: manages the changes in your code with time, other VCS tools being – Apache Subversion, CVS, Mercurial. It also provides collaboration between different members of the team.

The directory which contains your code and its dependencies is called a Repo (repository). In Git we have 2 different repos

  1. Local Repo: modified by an individual developer and resides in the local PC of developer
  2. Central Repo: acts as the main repo and resides on a server, all developers make changes to the local repo and push it to the central repo.
Git-work-flow
Workstations are local PC of Developers, Repository is the local repo of developers and on top we have central repo.

Some feature of Git :

  • Distributed Version Control System
  • Git uses SSH to connect to the central repo
  • In the local repo, there is a folder named [.Git] which contains info about your local repo
  • Many developers can work on a single project at a time
  • We always have a backup of code in local repos, in case the central repo fails

Click here to know about Git Commands

What is GitHub :

GitHub is nothing but a company that allows you to host your central repo on the Internet. You can even create a central repo in your local network but it can’t be accessed over the internet.

GitHub.com has created a user-friendly design and easy to manage the central repo, but at its core its just a central repo on the internet.

On GitHub, you can create a repository for every project you are working on. GitHub offers you unlimited public central repo(can be seen by anyone on the internet) and private central repo with a limitation of max 3 developers working on the project.

It’s always a good idea to create a readme file in your repo as it helps an unknown person to get a brief idea about your project. And people who have added their ssh key to the central repo server can modify the code.

So, in a nutshell, Git is a piece of software which helps to manage our code and GitHub.com is a website which allows us to use a feature of Git which is central repo.

Git – The Layman’s Guide : BASIC CONCEPTS and COMMANDS

GIT is basically a distributed repository (place to store code) where multiple contributors can work simultaneously and collaborate their work. It also serves as a Version Controls System (system that records changes to a file or set of files over time so that you can recall specific versions later).

GIT-branches

GIT allows you to revert files back to a previous state, revert the entire project back to a previous state, review changes made over time, see who last modified something that might be causing a problem, who introduced an issue and when, and more. It can also help in the situations where someone screwed up the code and it’s not working anymore. You can use the Version Control System to revert back to a safe version where everything was working perfectly normal.

GIT WORKFLOW

It is very important to understand GIT workflow. Let us learn a few key terms

Repository: This is your project (collection of source code). This is a GIT specific term and is a standalone unit for your project.

Working Directory: This is the working directory of your code. Here you edit your code and save changes.

Staging Area: When you are confident about your code and want to save it to the repository, You first bring it to the Staging area. You can bring your files in a sequential manner to the staging area.

Local Repository: When you have all the files you wanted to modify in the staging area and finally want to make changes to your repo, you save it to your local repo.

Remote Repository: Remote repo is a repository on a remote server which acts as a central repo for your project. Once you are 200% confident about your code. You move it to the remote repo.

Below diagram clearly explains how your code moves in the GIT environment.

GIT-data-flow-diagram

Commands in Detail :

  • git add: add a file from working directory to staging area
  • git commit: add files from staging area to local repo
  • git push: add files from the local repo to the remote repo
  • git fetch: get files from the remote repo to the local repo (not working directory)
  • git merge: get files from the local repo to the working directory
  • git pull: get files from remote repo directly to the working directory (same as git fetch and git merge)
  • git status: gives info about all the files which are yet to be committed (to local repo)

These are the basic commands to use while working with GIT. How we will see how to use Git to work with our code.

STEP BY STEP guide to initializing and working with GIT

Check weather GIT is installed

$ git --verison

 

Tell GIT about your identity

$ git config --global user.name "YOUR_USERNAME" 
$ git config --global user.email "me@samteck.net"

$ git config --global --list # To check the info you just provided

 

Generate SSH and add to your GitHub account (more on ssh keys)

$ ssh-keygen -t rsa -b 4096 -C "me@samteck.net"

$ ssh -T git@github.com   # check your ssh connection

– Copy the public ssh key (id_rsa.pub) from /.ssh folder in your home directory to SSH settings in your GitHub account

 

Lets GITify our first directory
Navigate to your working directory (in terminal) and initialize the directory with

$ git init

this will create a hidden folder in the working directory where info about the repo will stored. Also, there is a file called – .gitignore (it stores the info about the files in the working directory which need to ignored in repo like OS related files)

Add files to the staging area (Index: view of your working directory that is ready for commit)

$ git add .   # add all the files in that folder

$ git add *file name*   # add specific files to staging area

Before committing the changes we can check the status of the working directory (staged and unstaged changes)

$ git status

When all the changes are staged we can commit our code which will be then stored in the local repo. It is a good practice to add a message with every commit so that other users can see what modification has been made. Also, it’s better to sync your workspace with remote repo before committing to check that no other commits were made on remote repo by any other user.

$ git commit -m "First commit"

NOTE: every commit can be identified with a commit hash (SHA-1). On Github, you can view that commit from below URL

https://github.com/<owner>/<project>/commit/<hash>

Also, you can uncommit a change by

$ git reset HEAD~1

Add Remote Origin

Now we have created a local repo, but to add it to a remote repo we need to provide the address of remote repo

$ git remote add origin remote_repository_URL   # sets the new remote

$ git remote -v   # List the remote connections you have to other repositories.

$ git push -u origin master   # pushes changes to origin

Now you have successfully created a local repo and pushed it to the remote repo. If you open your GitHub account, you can see that your repo is available remotely on GitHub.

Useful GIT Commands

$ git diff   # To show the files changes not yet staged

$ git log    # view commit history

$ git clone remote_repository_URL   #download remote repo to working directory

$ git pull origin master         # update your local repo with changes on remote repo

$ git checkout <branch/commit>   # check out desired status of repo

When you git fetch, Git gathers any commits from the target branch that do not exist in your current branch and stores them in your local repository. However, it does not merge them with your current branch. This is particularly useful if you need to keep your repository up to date, but are working on something that might break if you update your files. To integrate the commits into your master branch, you use git merge.

Basically, this will be your control flow which you will be using most of the times.

$ git add .

$ git status # Lists all new or modified files to be committed

$ git commit -m "Second commit"

$ git push -u origin master

That’s all for the basic understanding of GIT. Thanks for reading.

Arduino: What, Who and How to use it | Learn Arduino Basic

arduino in original box

If you are a electronics hobbyist or if you are from engineering background then you have probably heard about ARDUINO. If yes then well and good and if not then I will tell you about it in the following post……..

arduino in original box

So first question

What is Arduino ?

Arduino is an open-source electronics platform based on easy-to-use hardware and software. It’s intended for anyone making interactive projects.
Basically it is an “open-source” means anyone can use and modify it and sell their own version without taking the permission of original owner.
It is a electronics board which helps you to

Make Your Own Hardware, Run Your Own Program

Who Should Use Arduino ?

Arduino can be used by any one whether a person with electronics as a interest or a enginnering student to make models or some person who wants to interact with its computer using sensors.
Arduino is an inexpensive board which is available for nearly $25 ( 1500) but having endless possibilities.

How to use Arduino ?

Using arduino is no big deal, technically its just like plugging your pendrive and start working with it.
But there are various steps to configure arduino which you can learn by Clicking Here.

arduino plugged into usb cable

So basically Arduino is an open-source microcontroller which you can use to play around and interact with the physical world present around you. So pursue you hobby and happy Arduinoing.