Version Control | Modules Unraveled
If you're still using FTP to install modules, update Drupal or make any changes to your Drupal codebase... STOP. Right now!
Git is a version control system with incredible features, and in this series you'll learn the basics to get you up and running.
Git has, on several occasions, saved me from myself when I accidentally deleted, modified or updated a module, causing an error. Git allows you to easily roll back changes to your codebase with a single command.