As repeated in many places in this tutorial we suggest when you are at beginning HTML stage that you use only the most software for Writing HTML, the most basic text editor you can find on your computer (for Windows, use NotePad; for Mac OSX use TextEdit or Plain Old HTML Editor).
Why not use Word or a WYSIWIG fancy tool? When you are learning HTML, we think you should be concentrating soley on learning the tags, the structures, etc. If you are trying to hard to be fancy in the beginning, you will get distracted.
At some point, you will become comfortable enough with writing your own HTML, that you will feel that the simple textb editors slow you down or are tedious to use. This is the point to be looking at some other software.
This is by no means a comprehensive list (try version tracker or C|NET) and just includes the versions of free HTML creation software we have tried or have been suggested by others.
For MS Windows
For MacOS X