From [Wikipedia](http://en.wikipedia.org/wiki/XML)

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> 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[4] produced by the W3C, and several other related specifications, all gratis open standards.[5]
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What are the historical reasons for calling the shorthand XML rather then the more natural EML?