Mark Wilson I am the creator of TopXML. I am available for international and local (Australia) contracts. I am a Solution Architect/Business Analyst. I have worked in IT in several countries (NZ, Australia, South Africa, UK) building and training teams for government and very large non-governmental organizations. I am ex-Microsoft Consulting Services. I wrote the first book on Microsoft XML published in 2000 called XML Programming with VB and ASP. Most recently I have been building tools for the SEO industry. Ask me for a 37 point SEO health-checkup for your website.
First posted :
03/29/2000
Times viewed :
156
General Guide to XML
Please provide feedback on this article to Mark Wilson
For descriptions of any of the words used in this article, please go
to the VBXML Glossary
Imagine
Imagine a world where programs can talk to each other. Where developers living many
years apart and in different countries using different languages can build programs which
can exchange data and can request information from each other. In this world a user can
ask your program for information from new sources on the internet which have become
available.
This is the promise of XML [Extensible Markup Language]. As HTML [HyperText Markup
Language] is a markup language which tells a Web browser how to display your HTML web
page, XML is a markup language which structures your information.
In this exciting world you can build a program which travels across the Internet and
accesses data on websites and databases all over the world. Before XML (or SGML, its
predecessor) a program would have to have intimate knowledge of the design of the program
or database which holds the data.
How would it benefit you?
For example let's say that you were looking for a list of all software developers who
can program in Visual Basic. One of the options you have is to index all the relevant web
pages on the Internet. But how do you tell if the page is listing Visual Basic programs,
Visual Basic programmers, Visual Basic discussion groups or Visual Basic development
companies? Sure, you could write an application which uses algorithms and dictionaries to
try to work it out based on the context, but wouldn't it be easier if the website (or even
an aplication!) had a way of explaining its content to your program?
Have you used a search engine and found exactly what you want the first time you asked?
If you used a search engine to search for the resumes of all Visual Basic programmers, for
example, you will get over 100,000 hits and only a few thousand would be appropriate. And
of those few thousand hits, only a few would actually be resumes, the rest being a
statement such as "email me for my resume".
I am sure search engine developers would like to see Web sites categorize themselves.
If there was a way in which Web sites could list their content and context, your program
would be massively simplified and search engines would become far more accurate.
In the broader XML scheme of things, this is the promise being made – that XML and
its derivatives will be capable of describing metadata (complex information and
relationships) in a way whch is mahine readable.
It is being designed in a discussion between the major interested groups and
individuals at the W3C [World Wide Web Consortium]. For more information on their
projects, go to: http://www.w3.org/Consortium/Activities.
NOTE: This link leads off the VBXML website and therefore it opens a separate
window.
A whole new world of information
A whole new world opens up which can encompass our imagination. Since XML is
extensible, it is hardly out the door and already another "language" called RDF
(Resource Definition Framework) is under development. It is based on XML and is designed
for manipulating metadata. For more information on RDF pleasee see
Still not convinced? VRML (Virtual Reality Modeling Language) is
being changed so that it is based on XML. That will mean that XML aware browsers can
display VRML. Hopefully we can kiss that extra download of the VRML viewer goodbye!
What about EDI (Electronic Data Interchange) and all the companies
whose job it is to sit in between you (the consumer) and the company which makes the
product you are looking for. If the company makes the details of their products available
on the web in XML/RDF, then you can conceivably imagine that the middle-person (otherwise
known as intermediaries, or on the internet they are known as infomediaries) could find
themselves being bypassed by you and your trusty internet browser! For more information on
the changes affecting the EDI industry, see page * for the
section called EDI.
And what about all those documents which don’t work because
they were made in one program and no other program can read it? Not a problem if the
format is XML. How about data stored on one OS (operating system) and your own OS
won’t read it? That’s no problem if the file is written in XML. Unknown graphics
files and future formats? Not a problem if the graphics format is XML based, because your
XML-aware browser will be able to read the XML and understand it
Microsoft's "push" or "channel" technology is
implemented in XML. Push delivrs your website to websurfers via "channels". The
technology that implements Microsoft's push technology is called CDF [Channel Definition
Framework] and CDF is written in XML. So when you create a push channel for your website
you are creating an XML file which tells another program details about your push channel.
Any program can access the CDF file because it is written in a text
file and it uses XML as its open format. Therefore, CDF is suitable to be a standard which
can be applied throughout the industry.
Textual markup makes your website more useful
Another immediately useful application of XML would be to markup
your data which is on your homepage or corporate web page.
So, the following paragraph:
You can have a discussion with Mark Wilson on the book XML and the
Internet for Visual Basic 6 at the Mannings website. Look for the author online section.
To meet other Visual Basic developers focussing on XML, go to http://www.vbxml.com
could be marked up to make its content more explicit to search
engines:
<review subject-type="book">You can have a
discussion with <AUTHOR>Mark Wilson<.AUTHOR> on the book <BOOK_NAME>XML
and the Internet for Visual Basic 6</BOOK_NAME> at the
<PUBLISHER>Mannings</PUBLISHER> website. Look for the <LINK_AREA> author
online section</LINK_AREA>. To meet other <USER_TOPIC>Visual Basic
developers</USER_TOPIC> focussing on <BOOK_TOPIC>XML</BOOK_TOPIC>, go to
<URL>http://www.vbxml.com</URL>.
Marking up text in this fashion could then enable a program to
search for XML documents or URLs which are useful to Visual Basic developers. I can
just hear the search engine developers and creators revving their engines!
