If you have a large website, a content management system can help to coordinate the efforts of multiple users.
When a website reaches a certain size, or if more than a couple of users need to work on the website at once, then working directly with HTML files on the web server and managing links between pages by hand can be a terrifying experience. This is where a content management system (CMS) comes in handy.
A CMS is a database-driven website. Content is created using a text editor (similar to MS Word) in an administrative area of the site, also known as the “back-end”. The CMS retrieves the content from the database and publishes it as a complete webpage on the site, also known as the “front-end”.
The main advantage of using a CMS based website is that it enables the user to manage content created by other users.  Content is generated dynamically, therefore the design of the site can be changed without having to worry about how the content will fit into it.