CMS = Content Management System
A content management system is a backend built into your website that allows you to edit pages or posts on your website using a visual editor (somewhat like a Word Document). A CMS will allow you to edit content in your pages and add posts to your blog, basically giving you (the business owner) a way to manage your website. A CMS gives your website a backend that you can login into to make changes to your website. Examples of a CMS are: WordPress, Joomla and Drupal.