Web site content generally falls into 2 categories:

Static content - web pages are coded in static HTML in much the same way as a Word document. To maintain the content of your site, you will need to know how to publish HTML documents and upload them to your web site. Alternatively, you will need to pay your web designer to do it for you.

Dynamic content - web page content is dynamically generated from information stored in a database. This content is managed and controlled by the owner through web based forms  accessed via a password protected area of your web site.