HTML editors (as opposed to WYSIWYG authoring tools) are designed to
speed up the process of writing HTML by hand. They do not allow you edit
the page visually, so you need to check your work in a browser. Many professional
web designers actually prefer to author HTML documents by hand,
and they tend to recommend the following:
TextPad (Windows only). TextPad is a simple and inexpensive plain-text code editor for Windows.
Sublime Text (Window, Mac, Linux). This inexpensive and up-and-coming
text editor looks stripped down but has a lot of functionality (like color
coding and full code overviews) that developers love.
Coda by Panic (Macintosh only). Coda users like its visual workflow, file management tools, and built-in terminal access.
TextMate by MacroMates (Macintosh only). This advanced text editor features project management tools and an interface that is integrated with the Mac operating system. It is growing in popularity because it is customizable, feature-rich, and inexpensive.
BBEdit by Bare Bones Software (Macintosh only). Lots of great shortcut features have made this the leading editor for Mac-based web developers.