Extensible Markup Language or XML has become of tremendous importance for the net. It is mark up language. It has the advantage of being both human-readable and machine-readable. It’s simplicity and usability has seen XML become the default language for many computing applications.
For example programs such as Microsoft Office, Open Office and Apple’s iWork all use XML-based formats. Many important API or application programming interfaces have been developed to process XML data. Since 2009 there has been a proliferation of XML-based languages including RSS, Atom, and XHTML.
XML based languages are not difficult to pick up. In a way XML is like BASIC in that both clearly differentiate content from code that manipulates content. In XML code is indicated by the tags <> and </>. Thus in the following code:
<p>Obama for President.</p>
The first <p> tag tells a computer to start a new paragraph and the closing </p> tells the computer to close the paragraph. The end user will only see:
Obama for President.
When coding it is important to remember that each page starts with an XML declaration such as:
<html xmlns="http://www.w3.org/1999/xhtml">
Many WYSIWYG editors will automatically generate this code for every page of HTML generated.
People ask about the value of knowing how to use XML and HTML now that the internet has seen a flurry of websites that offer free blogs and increasingly intuitive website templates. Obviously for serious website developers a knowledge of XML is essential. You won’t be able to implement any sophisticated design or functionality without some knowledge. The developers behind the BBC website use it extensively most recently to block VPN services automatically like this.
Otherwise the websites designed are going to be restricted by the limitation placed on all templates or ‘themes’. To be truly creative and innovative you must get back to basic principles and design from the bottom up – not fit in from the top down.
Moreover, you can drive a car without understanding how an engine works. However, when you have a breakdown such information can prove indispensable. Accumulating knowledge is never a waste of time. Ignorance is nothing to boast about.
Additional Resource: http://www.cedps.net/bbc-start-blocking-vpn-access-from-abroad/
