What is a CMS template ?

Question
What is a cms template and how do I use them ?
Answer
A CMS (Content Management System) template is a collection of files you can add to you website to change the way it looks and behaves. They will generally set the menu and content positions on your website. On most CMS websites you can alter the content on your site to show in the various editable locations within the template. CMS usually sites come with a default set of templates you can use to change the look and feel of your website. Examples of CMS sites are Wordpress, Joomla and Drupal.