Git - Basics

Git is different...

• Stores snapshots and not differences
• Stores and operates on local resources
• Checksums everything before storing - Git knows everything
• Git only adds data - takes talent to lose something!

Git - Basic terms

• Files can be either - Committed, Modified, or Staged
• Committed - stored on local DB | Modified - Modified, but not committed | Staged - marked for committing in the next snapshot
• Sections of Git Project - Git Directory, Working Directory, and Staging Area
• Git Directory - Where the project is stored (metadata/object db)
• Working Directory - local directory after checkout
• Staging Area - file in Git directory that stores info about what will go into next commit

Git - First Steps

Installation...
Check this Git Guide out for installing on different OSes

First commands...

• $ git config --global user.name "John Doe"
• $ git config --global user.email johndoe@example.com
• Check this to get a few more first time configuration options.

Git - the real deal

Most used/useful commands...

• Initializing a new repository -
  First, make a new directory
  Second, run - $ git init
• Start version control...
  Now, you can either pull/clone an existing repository(we'll cover this later)
  OR, start version controlling files by -
  First, adding to 'staging area' - $ git add *.html
  Then, committing to 'git directory' - $ git commit -m "first commit"

Git - usual flow

• Either clone an existing repository
  Clone - $ git clone git://github.com/schacon/grit.git *(optional) different directory name*
  
• Or, pull an existing repository
  First, initialize new repo - git init
  Then, link 'origin' with repository we're pulling from - $ git remote add origin git://github.com/cmcculloh/repo.git
  Then, set up additional remote tracking branches - $ git fetch --all
  Finally, pull everything to new repo - $ git pull origin master
• Checkout a new branch(working directory) - $ git checkout -b *branch name*
  (This creates a new branch and points to it)
• create a new file, or edit an existing file via an editor of your choice
• Once you're ready, add these files to staging and then commit
• PUSH to remote repository - $ git push origin(or any other name you set) *branch name*

Git - some useful commands/functions

Checkouts..
You can checkout entire commits, single files, and of course branches

• Commits - $ git checkout *commit id* (you can get it from $git log --oneline)
  This allows you to only view the specified commit, nothing will be saved in your repository.
• Individual files - $ git checkout *commit id* *filename*
  This allows you to edit AND commit an older version of a file, so in a way it's also a way to revert changes
• Branches - $ git checkout *branch name*
  This command helps you move from one branch to another - basically the branch becomes your working directory.

Reverting and Resetting Changes/Commits...

• $ git revert *commit id*
  This actually just undoes the changes brought on by the specified commit, and then makes another commit without those changes.
  So it doesn't actually 'revert' back to a previous state

Git - Remote Repos and Github!

Remote..

• $ git remote -v - lists your remote connections with urls
• $ git remote add *name of remote connection* *url to remote repository* - to add a remote connection

GITHUB Setup
Why git? GitHub provides best tools for sharing and commenting code - best for distributed development

• Create a GitHub Account, making sure to use your .edu address
• Use GitHub/Edu to request a free micro plan: these let us use private accounts
• Setup a GitHub SSH Key

Resources and Help
This is information overload - welcome to the I School. But don't worry

• Check http://git-scm.com/doc out for official git documentation!
• Here is an excellent tutorial for reference and more indepth git stuff - https://www.atlassian.com/git/tutorial/git-basics