aXe eM eL

Extensible Markup Language (XML) is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards.
XML's design goals emphasize simplicity, generality, and usability over the Internet. It is a textual data format with strong support via Unicode for the languages of the world. Although the design of XML focuses on documents, it is widely used for the representation of arbitrary data structures, for example in web services.
Many application programming interfaces (APIs) have been developed that software developers use to process XML data, and several schema systems exist to aid in the definition of XML-based languages.

Here is an example of :

XML Tree

XML Syntax

XML Table

Molecular Mechanics	Semi Empirical	Ab Initio
Very fast speed	Fast speed	Slow speed
Restriction parameter	Good accuracy	Very good accuracy
Very good protein modelling	Good protein modelling	Best protein modelling

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