If you have been editing your pages in frontpage or another editor like that and then transferring the pages via FTP, or writing documents in word and then sending them to (and likely paying) a webmaster to publish for you... having a content management system behind your site will be like getting handed a printing press in 1440.

It will allow you to publish pages directly through your browser, increasing productivity and publishing speed.  The best part is the people with the content knowledge have the ability to publish directly to your website.  No middle-people or technical webmaster folks need to be involved at all with your site content anymore.

When you have a content management system supporting your site, if you need to add a page - or 100 pages - you just add them!  Its as easy as opening a word doc and starting to type.  And of course if you see a typo or need to update a page that is currently live, you hit the edit button and make the change.  Or if you have a dozen people you'd like to contribute content, you set them up with accounts and a 5-minute tutorial and they are ready to roll.  And since its on the web if your content contributors are in 10 different locations around the globe that is no problem.

One of the aspects clients appreciate in their content management system is that you can edit the body area content on every single page through a very nice editor toolbar. 

When editing a page, you will see a toolbar in every textarea (large input areas for general text, like the page body).  It looks a lot like what you would have in an MS word document.  It is generating  the necessary HTML markup to apply various styles to your pages, add images, links, lists, etc.  You can always hit the source button to see what is going on behind the scenes and edit the HTML directly.  It is a plugin module on the Drupal CMS, called FCK editor (invented by Frederico Caldeira Knabben).

Editor, blogger and contributors with permissions will see a version like this:

There is also a “light” version I  sometimes used for user generated content like comments or user profiles to allow some formatting ability.  It only has items like bold, italics, and various heading formats available.

After you get used to publishing with your CMS in real-time, you'll never go back...