Git is a version control system that records changes to files over time by taking snapshots of the file system. It works by storing file changes as a set of snapshots rather than tracking file differences. This allows it to efficiently store unchanged files as links instead of re-storing the file. Some key Git concepts include cloning repositories, staging files, committing snapshots, pushing changes to remote repositories, branching to work on different versions, and stashing uncommitted changes. Submodules allow including other repositories within a repository.

1. Git
by Adham Saad

2. Contents
• What is Version Control ?
• What is Git
• Installing Git
• Setup Git for the first time

3. Contents
• Git Basics
o Cloning
o Staging
o Committing
o Pushing
o Reverting
• Git Branching

4. Contents
• Git Stashing
• Submodules
• Resources

5. What is Version Control
• Version control is a system that records
changes to a file or set of files over time so
that you can recall specific versions later.

6. What is Git
• The major difference between Git and any
other VCS (Subversion and friends included)
is the way Git thinks about its data.
• Conceptually, most other systems store
information as a list of file-based changes.

7. What is Git
• This is how other Systems thinks of files

8. What is Git
• Git doesn’t think of or store its data this way.
• Instead, Git thinks of its data more like a set
of snapshots of a mini filesystem.
• Every time you commit, or save the state of
your project in Git, it basically takes a picture
of what all your files look like at that moment
and stores a reference to that snapshot.

9. What is Git
• To be efficient, if files have not changed, Git
doesn’t store the file again , just a link to the
previous identical file it has already stored.

10. Installing Git
• on Ubuntu
$ apt-get install git
• For other OS
http://git-scm.com/book/en/Getting-Started-Installing-Git

11. Setup Git for the first time
• There are several servers for git , in which
we can create our repositories
o Github ( https://github.com/ )
o Bitucket ( https://bitbucket.org/ )
o Assembla ( https://www.assembla.com )
• Let’s go to bitbucket and create an account
for free.

12. Upload your Ssh key
• Go to
http://wiki.zhibek.com/wiki/Training/Git#SSH_key and
follow the steps to upload your ssh key to
bitbucket (
https://confluence.atlassian.com/display/BITBUCKET/A
dd+an+SSH+key+to+an+account )

13. New Repository
• Create a new repository from here
https://bitbucket.org/repo/create
• Follow the steps introduced to you from the
website to use the repo for the first time

14. Adding Files
• After cloning your repository , cd to it
• Add a new text file
$ git commit -m “your message”
• Here you have added your files to the
staging state but not to the server
$ git push
• You have added your file to the server

15. Adding Files

16. Sharing
• Let’s share one repository with all of us
• One of us will make changes , commit and
push
• The others should see his changes after
running git pull

17. Branching
• Branching in git is not used to solve day to
day issues , but usually for introducing new
releases , or for working on something
different than the master branch (like design)

18. Branching
• Create new branch
$ git checkout -b newbranch
• This is a shorthand for
$ git branch newbranch
$ git checkout newbranch
• This is also how to switch to an existing branch.
$ git checkout master

19. Stashing
• Sometimes , you didn't finish your task yet ,
but you want to pull the latest changes from
the server, and if you do you might have
conflicts. Here comes git stash .
• The stash command is saving all your non
committed changes to something like a
stack, and the you can pop it again

20. Stashing
$ git stash
$ git pull
$ git stash pop

21. Submodules
• Git also provides an easy way to include
libraries called submodules
• Suppose you want to add zend framework 2
library in your project , it is simply by running
the following

22. Submodules
$ git submodule init
$ git submodule add
git@github.com:zendframework/zf2.git
library/zf2
• Note that you might need to add your ssh
key to github too )

23. Submodules
• You can clone a repo with its submodules by
running
$ git clone <repo_ssh_url> -- recursive
• or after cloning it you can run
$ git submodule init
$ git submodule update

24. Resources
• http://wiki.zhibek.com/wiki/Training/Git (Please
update this page if you found something interesting)
• http://git-scm.com/book

25. Questions