About XML processors
XML processors are software programs that are used to parse XML documents and provide access to the documents' content and structure. XML processors can also validate the structure of XML documents and transform the documents into a variety of formats.
XML documents are text files that contain data that is formatted as a series of elements and attributes. Elements within an XML document can also be thought of as nodes of the document. The root element of the document is the root node, and all of the other elements are child nodes (or descendants) of the root node. Attributes are additional data associated with an element and are considered to be properties of the element. When an XML processor first loads an XML document, it parses the nodes of the document and places them in random access memory (RAM) in the form of a Document Object Model (DOM).
After an XML document has been parsed and loaded into the DOM, you can use the programmatic interfaces of the DOM to access and manipulate the XML document that the DOM contains. If an XSL Transformation (XSLT) is associated with an XML document, the XML processor can be used to apply the XSLT to the document to produce the specified output format.