XSLT extends the set of available functions with these:
Allows XSLT to access the nodes in another document
Returns the nodes that match object in the specified key
Returns the string representation of number using the formatstring specified and the decimalformat (or the default decimal format)
Returns the current context node
Returns the URI of the specified unparsed entity
Returns a string which uniquely identifies the specified node, or the first node in document order
Returns the value of the specified system property
Returns true if the specified element is available in the implementation
Returns true if the specified function is available in the implementation