Make calculate project

1. mkdir MathTool: Making directory named MathTool to save projects.

2. cd MathTool: Move to directory.

3. git init: initialize empty git repository.

4. ls -al: see all documents. it has ".git"

5. cd .git

6. ls -al: see inside of repository. it can control versions by using these complex mechanisms.

First you open terminal, you have to go to the root directory and type

source git-bash-for-mac.sh