xmlns:xsi

XML Schema Namespace Declaration

This is not an attribute, but a namespace pseudo-attribute. The value provides a URI to use for the @xsi_schemaLocation attribute. All namespace prefixes must be associated with a URL, and the prefix “xsi” has been set to the URL for the World Wide Web Consortium (W3C) XML Schema.

Used on Elements: <adoption>, <standard>

ValueMeaning
http://www.w3.org/2001/XMLSchema-instanceThe prefix “xsi” has been set to the URL for W3C XML Schema.
RestrictionThis attribute has a fixed value which may not be changed in the XML document.