"So What is a DTD?
The tags in the HTML language must be defined somewhere, right? They are defined in the DTD, which stands for Document Type Definition. In a DTD for HTML, all the HTML tags are defined. Everything is defined in the DTD -- the tags, the attributes, the possible values they can hold. Think of the DTD as the HTML tag dictionary: it lists all the tags, what they mean, and how they relate to each other.
Also, there are different DTDs because there are different versions of HTML:
HTML 4.01 Strict
HTML 4.01 Transitional
XHTML
Tidy fixes a number of common, and not so common, mistakes in HTML files. It does this by analyzing the markup in a file and comparing it to the HTML 4.01 specification. Depending on the options you specify, Tidy can fixes the problems it finds or it can generate a log detailing the errors.
The range of problems Tidy can fix is impressive. It can add missing or mis-matched end tags, correct tags that are in the wrong order, insert quotes around attributes, and can even add missing > to a tag. One of the few things Tidy can't do is add SUMMARY
Features:
* Suggests fixes and improvements for common errors found in HTML, XHTML and XML documents.
* Check multiple documents through the Batch Action Wizard.
* Ability to read settings from a default Tidy config file [new].
* Convert documents to XHTML and XML formats.
* Upgrade FONT tags to style sheets.
* Remove optional end tags.
* Indent / beautify tags, attributes and/or content.
* Change tags and/or attributes to uppercase or lowercase.
* Strip surplus tags in HTML documents generated using Word.
* Check for accessibility.
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HTMLtidy (otherwise known as Tidy) is an Amiga port of Dave Raggett's Tidy, which is a program designed to tidy up your HTML source files. It can adjust the layout of the source to make it easier for you to read, wrapping lines and indenting tables and lists etc.
However, that is not all that HTMLtidy does - it can also fix some of the more common HTML mistakes, including
* Missing or unmatched tags;
* End tags in the wrong order;
* Missing quotes round attributes;
* Missed / in end tags;
* Missing > closing tags;
and many
I’ve finally enabled a subset of HTML in my comments. In doing so, I had several requirements that needed to be fulfilled:
1. Entered markup must be valid to XHTML strict, to stop comments form breaking validation and keep things nice and tidy.
2. No presentational markup! I want to maintain control over how things look via my stylesheets—comments posted should only be able to use structural HTML elements.
3. Attributes should be restricted to those that add semantic meaning. Javascript event attributes and CSS related attributes should not be
As you know, XML is case sensitive: A tag defined in all uppercase letters needs to be written in all uppercase letters; a tag defined all in lowercase needs to be written all in lowercase. In XHTML, all tags are defined in lowercase. When writing XHTML 1.0 documents refer to the HTML 4.01 specification for information about specific tags and arguments, specificaly the "Index of Elements" and the "Index of Attributes." Any examples you see will remain nearly the same when converted to XHTML, except that you will need convert everything to