XML 101

Written by Jeff Jones

Continued from page 1

Tags (brackets, greater than, less than):

Just like in HTML, you use greater than (">") and less than ("<") signs called tags to indicaterepparttar opening and closing of an element.

Hank Aaron Babe Ruth


Elements arerepparttar 118062 basic building blocks of XML. They may contain text, comments, or other elements, and consist of a start tag and an end tag. Typically, XML elements are akin to nouns inrepparttar 118063 real world. They represent people, places, or things.

Hank Aaron Babe Ruth

Note that in XML, every opening element (i.e. "") must also contain a closing element (i.e. ""). The closing element consists ofrepparttar 118064 name ofrepparttar 118065 opening element, prefixed with a slash ("/"). XML is case-sensitive. While "" is well-formed, "" and "" are not. Also, ifrepparttar 118066 element does not contain text or other elements, you may abbreviaterepparttar 118067 closing tag by simply adding a slash ("/") beforerepparttar 118068 closing bracket in your element (i.e. "" can be abbreviated as ""). In addition torepparttar 118069 rules defining opening and closing tags, it is important to note that in order to create a well-formed XML document, you must properly nest all elements. The previous document properly nestsrepparttar 118070 "" elements withinrepparttar 118071 "" element, butrepparttar 118072 following would not be acceptable in XML becauserepparttar 118073 second "" element exists outside ofrepparttar 118074 "" element:

Hank Aaron Babe Ruth


Where elements representrepparttar 118075 nouns contained in an XML document, attributes representrepparttar 118076 adjectives that describerepparttar 118077 elements. The following document tells me that Hank Aaron's id is "1" and that Babe Ruth's is "2". This helps to describe these two employees.

Hank Aaron Babe Ruth

Note that in order to be well formed, all attribute values must be contained within quotation marks. id="1" is correct, while id=1 is not acceptable. This is a marked difference from standard HTML formatting that places much looser restrictions on what is acceptable.


Elements contain contents that give critical information about them. This information represents that entity itself in an XML document. Inrepparttar 118078 following document, Hank Aaron isrepparttar 118079 employee; Babe Ruth isrepparttar 118080 employee. Hank Aaron Babe Ruth

As you can see, XML and HTML are practically identical withrepparttar 118081 exception that XML is far less lenient when it comes to case-sensitivity, using closing tags, and properly nesting parent/child elements. This is excellent news for Web developers everywhere as it ensures that if you write well-formed HTML, you'll findrepparttar 118082 transition to XML virtually seamless.

To summarize, XML is a text-based meta-language that uses tags, elements, and attributes to add structure and definition to documents. It is similar to HTML in syntax and implementation, but different with regard to functionality. Where HTML allows users to control how documents are displayed, XML allows them to describerepparttar 118083 actual contents ofrepparttar 118084 documents. It is a markup language because it uses tags to mark-up documents and it is a meta-language because it uses these tags to give structure to documents that it in turn uses as a means of communication. XML is extensible because it enables users to create their own collection of tags (unlike HTML).

Now, why should you care about XML? If for now other reason, consider thatrepparttar 118085 World Wide Web Consortium (W3C),repparttar 118086 Internet's governing body, is considering a proposal to rewriterepparttar 118087 HTML 4 language in XML 1.0. As ofrepparttar 118088 time this article was written, XHTML had received endorsement byrepparttar 118089 director ofrepparttar 118090 W3C as a recommendation. This proposal, known as XHTML will require well formedness in all HTML documents. The W3C is a neutral standards body responsible for definingrepparttar 118091 future ofrepparttar 118092 Internet. They do not support every new idea that comes along, and we should view their full support of XML (or any technology), as a harbinger of where tomorrow's Internet will take us. Ignore XML if you will, but know that it is most definitely a legitimate technology that will revolutionizerepparttar 118093 way that we program applications forrepparttar 118094 Web

Jeff Jones For more information on XHTML, XML, and the W3C, check out the W3C website at http://www.w3c.org.

XML Is About To Rock Your World

Written by Bill Daugherty

Continued from page 1

The Internet became what it is today because HTML was accepted as a universal language for displaying images and text. The impact of XML will first be seen inrepparttar great improvement it will bring to search results on search engines.

Today's search engines produce a lot of irrelevant results. That's because, to a search engine, a word or phrase is just a pattern of letters without meaning. XML will eliminate a lot of this "garbage" search results by labeling content more thoroughly.

This may all sound like something out ofrepparttar 118061 distant future, but it will become our reality inrepparttar 118062 near future. The most amazing feats resulting from XML are those that we can't even image yet. The future will be an exciting time to live and XML will play a large role.

Bill Daugherty. Subscribe free to Bill's Internet marketing newsletter at:http://www.freeadsgalore.com

Visit Bill's latest project at: http://www.instantez.com

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