How to make a child theme in Joomla

One of the most usefull tools of Wordpress is using Child themes.  If you're looking for this feature in Joomla too, it is there just less publicized.
Child templates for Joomla .

Navigate to  Administrator-> Extensions->template Manager and selecting the template you wish to change.  Once you've checked the box next to the template, you can click the 'Duplicate' button to create a second copy of the template.  This will become the Override while the primary copy of the template remains the designated Master.

Cornwall Joomla development