Glossary 

DOM2-core interfaces

fundamental

DOMImplementation, DocumentFragment, Document, Node, NodeList, NamedNodeMap, CharacterData, Attr, Element, Text, Comment - all conforming implementations of the DOM (including HTML-only ones) must fully implement these interfaces.

extended

CDATASection, DocumentType, Notation, Entity, EntityReference, ProcessingInstruction - these interfaces are XML-oriented so HTML-only DOM implementation do not need to implement these objects.

Node Types

const unsigned short      ELEMENT_NODE                = 1
const unsigned short      ATTRIBUTE_NODE              = 2
const unsigned short      TEXT_NODE                   = 3
const unsigned short      CDATA_SECTION_NODE          = 4
const unsigned short      ENTITY_REFERENCE_NODE       = 5
const unsigned short      ENTITY_NODE                 = 6
const unsigned short      PROCESSING_INSTRUCTION_NODE = 7
const unsigned short      COMMENT_NODE                = 8
const unsigned short      DOCUMENT_NODE               = 9
const unsigned short      DOCUMENT_TYPE_NODE          = 10
const unsigned short      DOCUMENT_FRAGMENT_NODE      = 11
const unsigned short      NOTATION_NODE               = 12

Root, siblings, parents, children, ancestors, descendants

Example would be the best. Let's have this XML document:

  <?xml version="1.0"?>
  <test>
    <para>
      some text and <highlight>some highlighted text</highlight> in the first paragraph
    </para>
    <para>
      text in the last paragraph
    </para>
  </test>

Live objects in DOM

An object is live if any change to the underlying document structure is reflected in the object.

XML namespaces

• The DOM Level 2 supports XML namespaces by augmenting several interfaces of the DOM Level 1 Core to allow creating and manipulating elements and attributes associated to a namespace.
• In the DOM, all namespace declaration attributes are by definition bound to the namespace URI: "http://www.w3.org/2000/xmlns/". These are the attributes whose namespace prefix or qualified name is "xmlns".
• DOM Level 1 methods are namespace ignorant. Therefore, while it is safe to use these methods when not dealing with namespaces, using them and the new ones at the same time should be avoided. DOM Level 1 methods solely identify attribute nodes by their nodeName. On the contrary, the DOM Level 2 methods related to namespaces, identify attribute nodes by their namespaceURI and localName. Because of this fundamental difference, mixing both sets of methods can lead to unpredictable results.

Quolified name, local name, namespace URI, namespace prefix

Let's have MathML element <apply>. It's local name is "apply". Namespace URI for MathML is "http://www.w3.org/1998/Math/MathML". If we define somewhere on parent element namespace prefix "mathml" (with construction xmlns:mathml="http://www.w3.org/1998/Math/MathML"), all MathML elements should use this prefix, so this will look like <mathml:apply>, which is called quolified name.
Of course - if all descendant elements will be from the same namespace, we can define explicit namespace on appropriate root element of the fragment, i.e. <apply xmlns="http://www.w3.org/1998/Math/MathML">.

DOMString

• A DOMString is a sequence of 16-bit units.
• Applications must encode DOMString using UTF-16 (defined in UNICODE and Amendment 1 of ISO-10646). The UTF-16 encoding was chosen because of its widespread industry practice.

DOMTimeStamp

• A DOMTimeStamp represents a number of milliseconds.
• Even though the DOM uses the type DOMTimeStamp, bindings may use different types. For example for Java, DOMTimeStamp is bound to the long type. In ECMAScript, TimeStamp is bound to the Date type because the range of the integer type is too small.

Other data types

• Boolean (true/false)
• null
• unsigned long/short
• float

name attribute in DOM HTML

For historical and other reasons some elements in HTML (...) have attribute name. To confuse developers this attribute plays similar role as later introduced attribute id and in a lot of cases they can be used for the same tasks (like accessing nodes in document via their name/id). But from the DOM view these two attributes are strictly devided and you can be quickly lost. See namedItem() method for more detailed explanation.

Convenience methods and properties

A convenience method is an operation on an object that could be accomplished by a program consisting of more basic operations on the object. Convenience methods are usually provided to make the API easier and simpler to use or to allow specific programs to create more optimized implementations for common operations. A similar definition holds for a convenience property.

HTML and XHTML documents

From the developers point of view the most important difference between HTML and XHTML documents is that the XHTML documents are valid XML documents. See XHTML 1.0, chapter 4 for detailed explanation.

XPointers

The XML Pointer Language (XPointer) - the language to be used as a fragment identifier for any URI-reference that locates a resource of Internet media type text/xml or application/xml. XPointer, which is based on the XML Path Language (XPath), supports addressing into the internal structures of XML documents. It allows for traversals of a document tree and choice of its internal parts based on various properties, such as element types, attribute values, character content, and relative position.