The extensible markup language is in computing a manner in which a system annotates a document to enable syntactical distinguishability from other text. It defines a set of rules that are used for encoding documents in a manner that ensures readability for both the humans and machine too. The objective of the inventors was to provide much simplicity generality and friendly interface across the internet.
XML can be considered a textual data format that supports several different human languages with much support through the Unicode (Site Point, 2017). The term Unicode is used to refer to the computing industry standards that ensure that there are consistent encoding representation and handling of the text. The design of the XML is established to focus on documents but the language involved is broadly employed in the representation of arbitrary data structure, and a good example is a language used in the Web industry(Site Point, 2017).
The Extensible Markup Language is dated back to the development of Standardized Generalized Markup Language (SGML) in the 1970s by Charles Goldfarb when it became the ISO standard for indicating data in text-processing applications. This innovation happened when he was working with Ed Mosher and Ray Lorie at IBM (Anderson, 2004).
The purpose of establishing the Standard Generalized Markup Language (SGML) was to have vocabularies which could be employed to mark up documents with structural tags. However, more advancement were needed on the SGML as at that time it was assumed that only certain machine-readable documents should stay only in a machine-readable state perhaps for the longest duration possible. In the late 1980’s the development of Hypertext Markup Language by Tim Berners Lee in the late 1980s was a reaction to the complexity of the SGML for general useВ (Ibm.com, 2017). However, this innovation with time was not all round satisfactory due to its lousy fit in regards to data storage and interchange despite being so popular and rapidly adopted. This is what lead to the innovation of the XML which ensures a balance between the readability of the machine and humans while maintaining the flexibility to support the platforms and architecture independent data interchange (Ibm.com, 2017).
The reason why XML is considered significant in many aspects is due to various contributing factors. First, the language is extensible as it allows the user to be able to define a particular tag, the manner in which they occur and eventually how the data should be processed. Unlike the tags that are established in the HTML, the XML tags easily enable one to be able to define one particular set of tags(Ibm.com, 2017). However, it is also important to note that the XML is not only a language but rather a meta-language that would enable a user to create and define other languages in computing such as the RSS or the Mathematical Markup Language. The HTML which is very popular and common is closely similar to the XML in its purposes. Hypertext Markup Language is specifically the language established to ease the communication in web browsing as it allows one to describe the documents for display in a Web browser. It makes it easy for an individual to be able to prepare and share documents on the Web.
However, this language despite being of many benefits holds the disadvantage of being much cumbersome in performing a small everyday task such as displaying documents on a mobile deviceВ (Chris Collins, 2017). Thus the need for XML which is not only a language that is applicable in the Web but also in a variety of different another context. A good example is the Web Services use this extensible Markup Language to transfer requests and responses with very minimum human interaction. One can describe the HTML as the presentation language, and the XML is considered as the data-description language (Chris Collins, 2017).
Extensible Markup Language is a much smaller specification than the SGML and holds quite a significant number of a relative specification that is employed in the transfer and displaying of data in a browser. This related specification in XML will include the Extensible Stylesheet language which is abbreviated as the XSL and the Extensible Linking language which Is also known as the XLL.
A description of the type of XML document, typically expressed regarding constraints on the structure and content of the documents is regarded as the XML schema. The data description should be above and beyond the standard syntactical restrictions that are imposed by the XML itself (Chris Collins, 2017). Several of this sort of specifications are established by programmers to be of assistance to the user in the definition of the XML based languages. Currently, very many documents that are generated use the XML syntax. This computing language has established itself as the default for tools used in different offices for productivity. Typical examples of this include the Microsoft Office (Office Open XML), OpenOffice.org and the LibreOffice (Chris Collins, 2017).There are two versions of the Extensible markup language which include the first one XML 1.0 and was initially announced and defined in 1998.Despite this version undergoing numerous minor revisions, it was never given a new specific version number, and currently, it stands in its fifth edition. It is broadly used globally and highly recommended for the general use.
The other version of this computing language is the XML 1.1 which was published on February 2004 which was on the same day when the third edition of XML 1.0 was being published. Currently, the XML 1.1 is in its second edition as per the last publication of August 16, 2006 (Chris Collins, 2017).
What differs this from the pioneering versions are the additional features that were intended to make the XML as easy as possible use but some of this features are still controversial. The most notable changes were the enabling of line-ending characters that are employed on EBCDIC platforms. Moreover one can use scripts and characters that are absent from the Unicode. However, this has not been broadly implemented, and those that have been recommended to XML 1.1 are in for specific features that they contain and instead not the general use of XML 1.0. (Chris Collins, 2017).
Finally, the XML and its relative extensions have often been a subject of criticism for verbosity and complexity. When it comes to exchanging highly structured data between applications in a system the use of XML becomes complicated. The elemental mapping of the XML tree model to a type of programming languages can mainly be stubborn. However, as a move to loosen this aspect, an XML data binding systems were established that allows the applications to be able to access the XML data directly from the objects that represent a data structure. This is done by setting automatically a mapping that links in between the elements of the XML schema XSD of the documents and the members of a class that is to be represented in memory(Chris Collins, 2017). Other common criticism that is directed to XML involves the suggestion that brands the XML as a self-describing language in that it does not focus on representing highly structured data but instead focus on documents that possess both highly structured and relatively unstructured content. However, the strength of XML is embedded in its simplicity, and with this, it can ensure the structure and organization of information in an XML document are proper.
References:
Chris Collins. (2017).В A Brief History of XML. [online] Available at: https://ccollins.wordpress.com/2008/03/03/a-brief-history-of-xml/ [Accessed 2 Nov. 2017].Ibm.com. (2017).
IBM Knowledge Center. [online] Available at: https://www.ibm.com/support/knowledgecenter/en/SS6RBX_11.4.3/com.ibm.sa.xml.design.doc/topics/c_history.html [Accessed 2 Nov. 2017].
SitePoint. (2017).В A Really, Really, Really Good Introduction to XML SitePoint. [online] Available at: https://www.sitepoint.com/really-good-introduction-xml/ [Accessed 2 Nov. 2017].