A dynamic site is one that is written using a server-side scripting language such as PHP, ASP, JSP, or Coldfusion. In such a site the content is called in by the scripting language from other files or from a database depending on actions taken by the user.
A static site is one that is usually written in plain HTML and what is in the code of the page is what is displayed to the user.
Cost is generally lower up-front than a dynamic site.
A CMS or a ‘Content Management System’ quite literally allows you to control and manage the content within your web site – without technical training. Using this uncomplicated system you can very easily add, delete images and edit text in your web site on the fly.