I installed 3 installations of Drupal: 6,7,and 8 respectively. 

For an impending interview with the IRS as a Drupal developer, I installed 3 installations of Drupal: 6,7,and 8 respectively.  It ended up being easy with the open-source CMS Drupal into subfolders within my current Joomla 3 install on SiteGround!