From the article "Command is a behavioral pattern used to encapsulate actions in objects. This is highly useful when
you want to keep track of changes made to a model, for example in supporting multi-level 'do/undo.'"
This pattern by Fabio Arciniegas is presented in the January 2000 article Design Patterns in XML Applications on XML.com.
This pattern takes the original Gang of Four Command pattern and places it into an XML processing context.