Basic to intermediate Git and GitHub tutorial. Refer:
Cheatsheet: https://education.github.com/git-cheat-sheet-education.pdf
Git and GitHub alllows us to maintain the history of a project. Git is the version control system.
git init
This will create the hidden .git folder in your project.
These are the files and folders in the .git folder:

NOTE: blue ones are folders and white ones are files.
If I create a file names.txt in the folder and do:
git status
It will give:

To add files to a git repo do:
git add .
This is to add all files
git add <FILE_NAME>