A content management system or CMS is simply a way to edit your own site using a very simple interface (much like a word processing program such as Microsoft Word) without needing to know how to write code. Once your website has been designed, it is then up to you to manage it and keep it up to date. Of course, you could pay a web design company to manage your site and keep it updated but a much more cost effective way to maintain your site would be to use a CMS.
There are many options available when considering implementing a CMS. I can create your site using some of the most popular CMS platforms such as Joomla, WordPress or Drupal. In fact, this site has been built using WordPress. Other options I can implement include the use of a hosted content management system such as PageLime or Simple CMS.
It is also possible to build a completely custom CMS much in the same way a completely custom website would be created. However, unfortunately at this time I can not offer this service. Please check back here in case that changes.