Tidy's 30+ command line options are usually enough for most purposes. But they only scratch the surface of what this utility can do. You can tap into all of Tidy's power and functionality by using a configuration file. A configuration file is simply a text file listing various program options that gives you access to many of Tidy's extended features. These features include HTML to XHTML conversion, fixing the so-called HTML produced by Microsoft Word, adding ALT text to images, etc. There are even options for formatting markup, and for dealing with scripting languages. You simply specify the configuration file on the command line, and let Tidy do the rest. You can find complete descriptions of the options at the Tidy home page (see the end of this article for the link).
For all their usefulness, configuration files can be cumbersome to create. You not only have to sift through the options to find the ones you want to use, but you also have to spend time building a configuration file. And because no two sets of HTML files are exactly the same, you may have to create multiple files. Keeping track of them can be a chore.