Content Management System (CMS) Websites
Content Management System (CMS) websites can allow the user to do some updates themselves. These types of sites have a "front end" (the part that users see when they visit the website) and "back end" (the part that the administrator accesses to make modifications to the website). Ordinary HTML websites do not have an "administrator interface."
The free blogs one can set up on Blogger.com and WordPress.com are, in fact, simple CMS websites.
With a CMS website all the words and images making up the website are stored in a database. Consequently, you can change the look of the website without altering all of the website content. I don't want you to think I'm saying it's completely easy to change the look of your CMS website, that all depends on the complexity of your site, but with some very simple sites, you can change the look fairly easily.
CMS websites take up a lot more storage space on a server, compared to an HTML site. Getting that data from the webserver into a user's browser takes a lot more "throughput" (throughput is the amount of data flowing through the internet pipe). Both of these things are what drive the cost of website hosting. Thus, CMS website hosting can cost more than standard HTML Website hosting.
CMS websites are built by installing a framework of sorts, a "theme" on top of that (which is kind of the look of the site), and then adding or moving website content into that framework. There are different frameworks one can use, with the WordPress framework being the current industry standard. Other notable frameworks are "Drupal" and "Joomla" but there are many more. There are thousands of themes you can install on top of the framework.
Don't be confused by the fact that free WordPress blog sites are available on the WordPress.com servers. These sites use the WordPress framework, and themes, yes, but only allow a very limited amount of customization. The WordPress framework can also be installed on different servers to build very complex websites. A great many sites on the web are built using WordPress.
CMS frameworks have a lot of features built into them that users are looking for. Features that are more difficult to add to HTML sites. RSS feeds for content, RSS feeds for comments, search and sorting options making use of the site easier for your users.
You can administer some aspects of your CMS website yourself. To what extent depends on your creative and technical understanding. A common mistake made is that clients assume that they will be able to administer their CMS site with no one else's help. This is simply not going to be the case. If you need someone to build the site for you, you will likely need help going forward. New sections of the site, integrating new features, all will probably require the help of a web professional. Much of the administration of a CMS site is pretty technical.
And need I mention that graphic design, writing and search engine optimization skills don't come with the framework!
I have clients who are well versed in graphic design, good writers, who have a decent tech understanding, and they can do some of the management of their CMS sites. But most clients prefer the features a CMS site offers their visitors, but have me administer the site for them, because they recognize the value of my tech skills in creating the most professional presentation possible.
One can also build a regular HTML website and attach a CMS blog to it. The regular HTML website and the blog can look exactly the same, or be complementary in design. That way you get the benefits of the lower up-front costs of building a standard HTML website, but you still have the benefits of being able to add your own content to your blog as it becomes available.
It is generally more time consuming to prepare a CMS framework and create/move content to fill it than it is to create a standard HTML website. So you can count on higher up-front costs. Depending on how technically proficient you are, and how much upgrading you intend to do, a CMS site may cost less to maintain than a standard HTML site. The best thing to do when you are working with me is to discuss what you want your site to do, how you want it to look, how you intend to use it, and your budget. I'll let you know what type of site you'll be able to afford and design the best site possible.