apt remove vs purge (to delete a Ubuntu package)

In order to remove and re-install a package

• $ sudo apt remove --purge {package}
• or $ sudo apt purge {package}

• $ sudo apt clean
• $ sudo apt install {package}

Difference betweeb remove and purge

• Reference
• http://askubuntu.com/questions/231562/what-is-the-difference-between-apt-get-purge-and-apt-get-remove
• remove: Packages installed are removed (Does NOT include configuration files)
• purge:  Identical to remove except that any configuration files are deleted too.
• However, any configuration files inside the user's home folder(/home) will not be touched. Only the files under /etc will be deleted by using purge. 

Removing ppa

• Reference
• https://websetnet.com/ko/remove-ppa-ubuntu-linux/
• $ sudo apt-add-repository --remove ppa:{ppa information}