A system for the storage, retrieval, editing and eventual display of content on a website.
In the earlier days of web design and the Internet end users were often unable to edit their own websites. Entire sites would be built from lots of individual HTML pages which were relatively difficult to edit.
Powerful design tools and editors started to enter the market but were still often either expensive or difficult to use (or in the case of simple solutions such as Word Processors not very good!). As a result it was still beyond the capability of many business owners to update the latest information about their business without calling on the assistance of their original web designer.
Content management systems revolutionised this process. They allowed designers to focus primarily on the visual and structural elements of the site. Most systems (WordPress, Joomla and Drupal are three extremely popular CMS) provide an easy to use what you see is what you get (WYSIWIG) editor for users. It is then possible to edit pages and entries without even seeing the HTML and CSS code which makes up the actual design of the site and has brought self-editing within the reach of most businesses.