For doing web design two main type of programs are used. One to create and edit the graphical objects like images, photos, logos, etc. and another that is used to construct the html page source code. The latter are called HTML editors.

As it is an ordinary ASCII text file, the HTML can be created or edited using any text editor, like Notepad for example. However, there are also specialized programs that are dedicated for web design – html editors. Some of these editors may have WYSIWYG feature – What You See Is What You Get. These editors allow you to work with the html code directly or via the page layout workspace automatically generating the html code while you change the page layout.

Text editors useful for HTML code editing:

ConTEXT - great text editor that has good syntax highlighting features. The ConTEXT editor is free and can be found at http://www.context.cx
Crimson Editor - http://www.crimsoneditor.com/
Note Tab - http://www.notetab.com/

HTML editors:

TSW WebPad.NET - Lightweight HTML, CSS and PHP editor
Bluefish - a powerful editor for experienced web designers and programmers.

WYSIWYG editors:

NVU - free WYSIWYG editor, http://www.nvu.com. Nvu is 100% open source and released under the Mozilla Public License (MPL).
Adobe GoLive CS2
Macromedia Dreamweaver 8