XML comes from eXtensible Markup Language (“Extensible Markup Language” ). It's about a metalanguage (a language which is used to say something about another) extensible label that was developed by the Word Wide Web Consortium (W3c ), an international commercial company that develops recommendations for the world Wide Web.
XML is an adaptation of SGML (Standard Generalized Markup Language ), a language that allows the organization and labeling of documents . This means that XML is not a language in itself, but a system which allows to define languages according to the needs. He XHTML , he MathML and the SVG These are some of the languages that XML has the ability to define.
Databases, text documents, spreadsheets and websites These are some of the fields of application of XML. Metalanguage appears as a standard that structures the exchange of information between different platforms.
Experts point out several advantages that derive from the use of XML, such as: it is extensible (new tags can be added after document design); Your analyzer is standard (does not require changes for each version of the metalanguage); facilitates the analysis and processing of XML documents created by third parties.
Among the languages created with XML, the XSL (Extensible Stylesheet Language ) and the XLINK (which tries to transcend the limitations of hypertext links in HTML).
The validity of the documents (that is, their structure syntactically developed) the specified relationship between the different elements depends on an external document or definition.
As analyzed, XML presents a series of very attractive advantages for developers, especially because it allows to relate applications from different languages and platforms; However, this can be seen as a double-edged sword, since it does not encourage the search for compatibility. The universality that XML pursues may never come if instead of taking advantage of it to solve problems, new ones are generated knowing that they will have a solution.
Since, in large part, the usefulness of a tool It depends on the creativity of the user, it is impossible to summarize all the XML applications. In short, it can be said that it offers the possibility of structuring and representing data. Currently, it is common for programs to include configuration files in this format; Such is the case of Apache and applications created with .NET technology (from Microsoft).
When developing a program with a graphical interface it is necessary to organize all the images so that they are loaded as they are needed, and XML is very helpful in these cases: it allows grouping, labeling, specifying their location and relating them to other data, according to the needs of the designers.
But in addition to facilitating the organization of the resources and the configuration of a program, XML plays a very important role that is, without a doubt, its strong point: it allows you to communicate with other applications, from different platforms and regardless of the origin of the information in common. You can have, for example, a program running on Windows with a SQL Server database, and another on Linux with Oracle, both sharing data thanks to an XML structure.
The Web services, a very common concept in this era, are components of the Net that offer the possibility of carrying out a varied series of operations, through concrete methods that take advantage of the XML metalanguage for their communications, thanks to which any platform can make use of its advantages.
Finally, XML is one of those tools that despite its low complexity hide great potential, thanks to being easy to use and undeniably useful.