How to connect a directory to Github

source https://kbroman.org/github_tutorial/pages/init.html

1. Move to your local directory of interest.
2. $ git init : to initiate git function in the directory.

3. $ git add xxx : add a file (e.g. .gitignore) to be tacked by git.

4. $ git commit -m "..." : commit the change.

5. Generate a new project on Github, and obtain the address under 'clone' (No need to create README)

6. $ git remote add origin [repo address]

7. $ git push -u origin master

*Note: the address starting with "git@.." is for SSH, while "https://" is for the use without it.