.
https://linuxize.com/post/bash-if-else-statement/
https://bash.cyberciti.biz/guide/While_loop
https://linuxize.com/post/bash-until-loop/
https://devhints.io/bash
http://johnstowers.co.nz/pages/bash-cheat-sheet.html
https://github.com/LeCoupa/awesome-cheatsheets/blob/master/languages/bash.sh
