Simple Outline XML (SOX) is a compressed way of writing XML.
SOX uses indenting to represent the structure of an XML document, eliminating the need for closing tags.
Example
The following XHTML markup fragment:
... would appear in SOX as:
html> xmlns=http://www.w3.org/1999/xhtml head> title> Sample page body> p> A very brief pageSOX can be readily converted to XML.
References
Simple Outline XML Wikipedia(Text) CC BY-SA