Every web developer states that:
"I am a web developer. It is a waste of my time and talent to take a Microsoft Word document and cut and paste content to a web page every time the client wants a change."
If this statement resonates with you, then you need to be familiar with CMS. They're an easy and powerful way to put publishing power in your users' hands, so that you can focus on less tedious, better paying work. All you have to do, is help the client set up their CMS, choose and customize their templates, and leave the content creation and maintenance to them. A CMS is often at the core of both small business websites and corporate websites.
Static site generators, on the other hand, allow developers to share the power with the client. Projects and platforms such as Harp.io allow clients to use the tools they're already familiar with, such as Dropbox for example, to publish changes to their own site and avoid the hassle...