Livejar

In the heyday of HTML, browsers were designed specifically to display the results of HTML code that they were given. Those browsers displayed HTML through a set of hard-coded rules: for example, “at the appearance of <p>, skip a line and continue dis- playing the content.” Rules such as these allowed HTMLauthors to take “legal” short- cuts—or, more accurately, to write plain, sloppy code. According to the rule just stated, there is no need to close a paragraph using </p> as long as the next one starts with <p>—the rule will work and the content will be displayed properly. This is not the case with XML—and remember, XHTML is an XML language.  XML documents are parsed before being displayed. Since XML languages can contain ele- ments and attributes that the browser may not already be familiar with, all elements and attributes must be checked before being displayed. An XML parser does this checking; it checks to make sure that the document is well formed. (...

In 1996, at the height of the browser wars, the W3C had also begun working on the eXtensible Markup Language (XML), a separate project from HTML, but one whose background is important to understanding XHTML, a combination of XML and HTML, and more importantly, the subject of this book. When the XML project began, the aforementioned SGML, a complex method of structuring text for later processing, was being used primarily for very large projects— those involving millions of pages of documents. Recall that HTML at this time was a severely limited way of formatting documents for transport over the Internet and for display via a Web browser. The W3C’s objective in developing XML was to create a markup language that had the power, but not the complexity, of SGML. Defining XML The following excerpt from “XML in 10 points” (located at www.w3.org/XML/1999/ XML-in-10-points) defines the parameters of XML: XML is a method for putting structured data in a text file. For “structured d...

Web development is a broad term for the work involved in developing a web site for the Internet (World Wide Web) or an intranet (a private network). This can include web design , web content development, client liaison, client-side/server-side scripting, web server and network security configuration, and e-commerce development. However, among web professionals, "web development" usually refers to the main non-design aspects of building web sites: writing markup and coding. Web development can range from developing the simplest static single page of plain text to the most complex web-based internet applications, electronic businesses, or social network services. For larger organizations and businesses, web development teams can consist of hundreds of people (web developers). Smaller organizations may only require a single permanent or contracting webmaster, or secondary assignment to related job positions such as a graphic designer and/or information systems technic...