By Saquib Khan, for Git and GitHub session conducted by DSC UCEK

1. Git and GitHub
By Saquib Khan

2. About Me
In the industry for ~15 years
Solving problems for our customers and users
Mentor and Coach, Open Source Collaboration
Currently Senior Engg Mgr in Github India, prior to that with Microsoft, Intuit,
Ciena, Huawei
Technologies mostly worked on Java, C#, C/C++, ReactJs, Angular, RoR, NodeJs,
AWS, Azure, iOS, Android etc.

3. More About me and Contact
https://www.linkedin.com/in/saquibkhan
https://github.com/saquibkhan
saquibofficial@gmail.com

4. Problem 1: Maintaining history of changes made on a file,
what changed?
when change was made?
why it was made?
Developer want to travel back and forth in time and get any version of the file for the
given version/time.

5. Version Control System (VCS)

6. Problem 2: More than one developer (a Team) want to collaborate working on same files and
also able to maintain history of file versions/changes
Who made the change?

7. Types of VCS: Centralized (CVCS)

8. Types of VCS: Distributed (DVCS)

9. Short History of Git
● Creator - Linus Travold, also creator of Linux Kernel
● In 2002, the Linux kernel project began using a proprietary DVCS called BitKeeper(similar to Git).
● In 2005 BitKeeper was no longer free.
● Created Git based on some of the lessons they learned while using BitKeeper. Some of the goals of the new system were as
follows:
○ Speed
○ Simple design
○ Strong support for non-linear development (thousands of parallel branches)
○ Fully distributed
○ Able to handle large projects like the Linux kernel efficiently (speed and data size)

10. Git - CVCS or DVCS ?

11. How its Different?

12. Git : The core Idea
One major thing which Git did differently apart from all other VCS was
how it stores the Data
Differences vs Snapshots

13. Differences

14. Snapshots

15. Three Sections and States of Git
modified
staged
committed

16. How to use Git?

17. Git Command Line Tool Install
Downloadable/HomeBrew Mac, Linux, Win - https://git-scm.com/downloads

18. Git First Time Setup
git --version
git config --global user.name “Saquib”
git config --global user.email saquibofficial@gmail.com
Ref - https://git-scm.com/book/en/v2/Getting-Started-First-Time-Git-Setup

19. Create a New Repo or Get an Existing one
git init
git clone https://127.0.0.1/existing_repo
The default branch for new repo is main and for older repos it was master
(with ref to GitHub git server)

20. The three Stages
git status
This will show up status of working directory
Files Modified and Ready to be Staged
Files Staged and Ready to be Committed

21. Modified -> Stage -> Commit
git status
git add file1
git commit -m “short msg desc what and why change is done”

22. History
git log

23. Check a version in History
git show 760359b66d6f7620adbeab0bd602c0d0aa9e5852

24. Go back to a version in History
git checkout 760359b66d6f7620adbeab0bd602c0d0aa9e5852

25. Day to Day Working on bugs and Features
Best Practice - Always have a new branch for every bug or feature
Cost of creating a new branch - 4 bytes

26. Create a New Branch
git checkout -b <branch name> -t <remote>/<default branch>
git checkout -b branch_name -t origin/master

27. Working with Remote Server
git remote -vv
git remote add origin https://github.com/saquibkhan/javaFlameGraph.git
git remote add upstream https://github.com/saquibkhan2/javaFlameGraph.git
git remote add server2 https://github.com/saquibkhan3/javaFlameGraph.git

28. Push
git push <remote> <branch>
git push origin branch_name

29. Pull
git pull <remote> <branch>
git pull origin master

30. Pull (another way)
git fetch <remote> <branch>
git rebase <remote>/<branch>
git fetch origin branch_name
git rebase origin/branch

31. GitHUB

32. History
2008 founded in San Francisco, California
2018 Microsoft acquired Github for nearly 7.5 billion USD
Aug 2020 Github India, Hyderabad Office started
https://github.com/about/careers
~70% Employee are Remote

33. GitHub Profile

34. Repository Page

35. Commits and Branches

36. Pull Requests, Code Reviews, Approvals, CI,CD

37. Issues

38. Actions (CI/CD)

39. Insights

40. Education/Students
https://education.github.com/

41. Extend GitHub
https://github.com/marketplace

42. Github Sponsors

43. Refernce
Book - https://git-scm.com/book/en/v2