Here are some free WYSIWYG HTML Editor software and online tools. You can edit the output content and HTML source code and preview it.

ConstEdit is a free HTML5 editor that lets you create & edit HTML & HTML5 documents & web pages. This word processor comes with a rich editing toolset.

The language of the Web–Hypertext Markup Language, or HTML–is actually pretty simple. And there are plenty of Web site editors to further simplify the process.

Dreamweaver normally sells for several hundred dollars, but it appears to be worth it. If one is into Linux, the HTML editor software is free. A favorite and a very good piece of software is KompoZer.