If you are having problems unzipping a file, it may be that your system has already unzipped it for you during the download without removing the ".gz" suffix. You may have to rename the already unzipped file by hand.
Each W3C Technical Report includes a "Status of this document" section near the front. In this section, you will find information about where to send comments.
Specifications index elements differently. Most specifications include one or more DTDs, or document type definitions. A DTD defines the syntax of a language in technical terms. Some XML specifications include XML Schema definitions; a schema is another way to define the syntax of a language. Some specifications also include a simple list of element and attribute names for convenience. W3C does not have a single page where all of the elements and attributes of all W3C Technical Reports are listed.
Each specification defines its own DTDs, often in an appendix of the specification. There is a list of links to various W3C-defined DTDs in the W3C site index.
If you use a library (like libwww) and include it in the source code, or compile/link to it, you must also include the copyright license. However, if you merely provide a compile option you are not obligated to include our license. Any subsequent party that links or includes against the library is obligated to include the license. (If you include the option, you might do your users a favor by pointing to it yourself.) To restate our policy: it is the responsibility of the person who causes our software to be included in subsequent distributions (either in source, object, or executable code) to abide by our terms.
IPR Notice and Disclaimers General web site copyright, trademark, and legal disclaimer statements. Document Notice/License Information on reproducing W3C work including notes, submissions, recommendations, proposed working recommendations, working drafts and documentation. The document notice does not permit derivative works so as to prevent misleading alterations to our specifications that are then associated with the W3C. Software Notice Information on using and modifying W3C software. This is an open/free license; software under this license can be used with GPL licensed software, or proprietary licenses.
The original author of the document. Many documents are created by the W3C and we consequently hold the copyright. Owners who allow their works to be published on the W3C site retain the copyright, but agree to the W3C license for the redistribution of those materials from our site.
The STATUS of a W3C document is very important. It details its purpose, how the document was created or received, whether we are allocating resources to an activity related to the document, whether we have editorial control over the document, and how it may be referenced by other activities or documents. We disapprove and will act upon the misrepresentation of our work with respect to authorship, endorsement, or status.