HTML provides a means of displaying and accessing information on the World Wide Web. Web pages may also be viewed in a browser without the user being connected to the Internet. The use of this form of document for information exchange has become more common. Modern email clients may send and receive HTML-formatted messages. HTML is one of the methods of transforming XML into a browser document. Even if you do not plan to web publish XML, you may still find this chapter useful for these reasons.
HTML uses Hypertext Transfer Protocol, URIs, fragments, and a tag-based language to display the items located by the URI and requested by the HTTP protocol. HTML is also based on Standard Generalized Markup Language (SGML). The elements and attributes are similar to XML, however the empty elements in HTML do not always adhere to the strict rules of XML. Therefore, XHTML converts some of these elements for compliance with XML. All the elements shown here will be in XHTML format with a description of the original HTML form, if necessary. Browsers may be forgiving in allowing attributes to be unquoted, but all of the attributes will be quoted here for conformance with XHTML.
When designing HTML documents, the W3C recommends these considerations: 1) separate the structure and presentation; 2) design for universal access—this means for Braille, text readers, and language differences; and 3) design for the fastest load and rendering of the pages—especially if target users are using dial-up connections.
While this chapter is not a comprehensive HTML or XHTML reference, it provides you with an overview for using HTML with FileMaker Pro and XML. HTML can be used to present the results of a request to Web Companion. The <form> element and its associated elements can be used to submit information to your databases to find records, create new records, and edit and delete records. The two documents that may help you the most with details about HTML and XHTML are "HTML 4.01 Specification," http://www.w3.org/TR/html401, and "1.0: The Extensible Hypertext Markup Language XHTML," found at http://www.w3.org/TR/xhtml1.
The element and attributes names in this chapter are listed as uppercase (<ELEMENT ATTRIBUTE="">) and as lowercase (<element attribute="">). Often HTML is written in uppercase to distinguish the elements from the XML elements, which are lowercase. However, XHTML should use lowercase for the HTML elements and attributes. If you use element names in uppercase, lowercase, or mixed case, remember to be consistent in the XML document. Be especially consistent in the case of the start tag and the end tag for the same element. XML is case sensitive.