Linux: If it's not installed on the linux distribution you're using, install by
$ sudo apt-get install git
Windows: Download git windows version ([link](http://msysgit.github.io/)) and install and use git bash

After installation, configure you name and email by
$ git config --global user.name "Your Name"
$ git config --global user.email "[email protected]"

$ mkdir learngit
$ cd learngit
$ git init  
	Initialized empty Git repository in /Users/michael/learngit/.git/
Create the files in the repo directory you'd like to add, e.g., readme.txt. Be caucious about the encoding method for windows: using UTF-8 without BOM
$ git add readme.txt
$ git commit -m "wrote a readme file"
	[master (root-commit) cb926e7] wrote a readme file
	1 file changed, 2 insertions(+)
	create mode 100644 readme.txt

$ git status
$ git diff filename
$ git log <--graph> <--pretty=oneline>	// showing commit history
$ git reset --hard commit_id //e.g. HEAD^  // reset to the previous version; HEAD denotes the current version; ^,^^,^^ previous versions
$ git reflog // showing history with commit_id
$ git checkout -- filename		
	// checkout filename in repo to workspace: discarding changes in workspace filename or restore deletion
$ git reset HEAD readme.txt
	Unstaged changes after reset:
	M       readme.txt
$ git rm test.txt
	rm 'test.txt'
$ git commit -m "remove test.txt"

a. Register an account if not yet.
b. create SSH Key for the communicatoin between local and remote
	$ ssh-keygen -t rsa -C "[email protected]"
c. create the empty remote repo on github
d. push an existing repository from the command line
	$ git remote add origin https://github.com/liborutgers12/learngit.git
		//The remote repo are called "origin"
	$ git push -u origin master
		//-u for association for the first time; 
		//Branch master set up to track remote branch master from origin.
	$ git push origin master
		//no need for -u parameter
e. clone from a remote repo
	$ git clone [email protected]:michaelliao/gitskills.git
f. pull a remote branch
	$ git pull <remote> <branch>
	$ git branch --set-upstream dev origin/<branch>
	

$ git remote -v //remote repo detailed info

branches are basically pointers
$ git branch dev	//create new branch "dev"
$ git checkout dev	//switch to "dev" from "master"
$ git branch		//check existing and current branches
revise/add files to "dev" and commit; 	
switch back to master branch and merge dev to master, and delete branch "dev"
$ git checkout master
$ git merge dev
$ git branch -d dev