IGNOU BCA 5th sem Solved Assignment - What is XML? Why is it needed even though you have HTML?

What is XML? Why is it needed even though you have HTML? Create at least five instances of your friend’s data using a XML page. The list can contain name and date of birth of the friend. In addition, each friend will have at least one phone number and address. Create the DTD for the XML document you have created.

Ans

The buzz-word "XML" is beginning to pop up all over the Net, and in the Goodies e-mail box. People are wondering what this new language is and how it's going to effect the way people write. To be honest, I was wondering the same thing until I started looking into it.

     Avid readers of HTML Goodies already know that XML is mentioned in two other tutorials (as of 5/11/98): HTML 4.0 and the Active Channel Tutorial. The language is starting to make a few in-roads into the Web and that makes a few people nervous. As one Goodies reader put it, "I just got pretty good with HTML, and now they're bringing out this thing." I feel your pain. Believe me, I do. It means that I will need to learn it all first so that I can teach it to you.      So, here we go. This first tutorial is an introduction to what the heck this XML thing really is.
     SGML is not a language per se, but rather a series of commands that are all understood by another program. A similar example would be JavaScript. By itself, there's not much to it, but if you use the JavaScript commands in a particular order and then allow a Web browser to read it, you get some neat effects.

     In five words or less you mean? That can't be done. XML are initials for EXtensible MarkupLanguage. Seems strange that the first word is "Extensible," yet they use the "X" to denote the word. My guess is that "XML" looked a lot cooler than "EXL."

     You may not know this, but HTML and XML are brother and sister. Their mother is SGML. SGML (Standard Generalized Markup Language) is the overriding language that produced both XML and HTML.

     My personal opinion is that nothing is wrong with it. It was the first computer language that could be understood and used by the masses. It gave the Web to the common person. But those in the XML know claim HTML is clunky. They say it's become static. There's not a lot more one can do with it. Supposedly XML will allow a lot more flexibility in your Web pages. There will also be more flexibility in your HREF links. You'll be able to create cross-references and threads and other fun stuff. At least that's what the brochure says.

     HTML is not dead, nor is it breathing funny. HTML will be around for years to come, if not forever. It is still a solid format and too many people know it. I believe I will be able write HTML and post Web pages as long as I live using HTML alone. They just might not be as fancy as other pages.

In late 2000, Earthweb (now DICE.com) decided to go to a fully XML format. Many sites melded to the format well and ran smoothly. HTML Goodies was a different story. I've set the site up in a hierarchy format and it just wouldn't fit neatly into XML. Every time we tried to take it live, the number of errors forced us to go back to the HTML format. It was such a pain, in fact, that we decided to scrap the XML version altogether. That didn't sit real well with those who put their hearts and souls into the new site.