XML —

HTML

Nearly every computer user is familiar with HTML. HTML is a fairly simple language that has helped promote the wide usage of the Internet. HTML has come a long way since it was originally designed so that scientists could use hyperlinked text documents to share information. Let us begin by looking at HTML's original version.

Early HTML

In its original conception, HTML was supposed to include elements that could be used to mark information within the HTML document according to meaning. Tags such as <title>, <h1>, <h2>, and so on were created to represent the content of the HTML document.

How the marked text would actually be interpreted and displayed would depend on the Web browser's settings. Theoretically, any two browsers with the same user settings would present the same HTML document in the same way. This flexibility would enable users with special needs or specific preferences to customize their Web browsers to view HTML pages in their preferred format-an especially useful feature for people with impaired vision or who are using older Web browsers.

In this scenario, the HTML developer uses tags based on an HTML standard that are displayed according to the user's preferences. For this to work, it must be based on a standard for HTML. The current Web standard can be found at http://www.w3.org.

Problems with HTML

HTML has proved to be a great language for the initial development of the Internet. As the Internet matures, the need has developed for a language that can be used for more complex and large-scale purposes such as fulfilling corporate functions, and HTML quickly fails to meet the mark. Let's look at some of the problems with HTML.

Conflicting standards

In 1994, Netscape created a set of HTML extensions that worked only in Netscape's Web browser. This was the beginning of the browser wars, and the first casualty was the HTML standard. Using these extensions, Netscape could now allow the author of the HTML document to specify font size, font and background color, and other features. Eventually, Netscape added frames. Of course, all of these extensions would not display properly in any other browser. The HTML extensions were so popular that by 1996 Netscape was the number one browser.

Although Netscape won a major victory, Web developers and users suffered a major loss. In addition to the problem of handling nonstandard extensions, different browsers handle the standard tags in different ways. This means that Web designers now have to create different versions of the same HTML document for different Web browsers. The extensions force users to accept pages that are formatted according to the author's wishes.

In most browsers, you can create default settings that will override the settings in the HTML pages. Unfortunately, most users do not know how to use these settings, and if you do set your own defaults, most pages will not display correctly.

Creating HTML documents that will appear approximately the same in all browsers is a difficult, and at times impossible, task. For information about this topic, see the Web Standards Project at http://www.webstandards.org.