09 April 2002

Glossary

Editors:
Arnaud Le Hors, W3C
Robert S. Sutor, IBM Research (for DOM Level 1)

Several of the following term definitions have been borrowed or modified from similar definitions in other W3C or standards documents. See the links within the definitions for more information.

16-bit unit
The base unit of a DOMString. This indicates that indexing on a DOMString occurs in units of 16 bits. This must not be misunderstood to mean that a DOMString can store arbitrary 16-bit units. A DOMString is a character string encoded in UTF-16; this means that the restrictions of UTF-16 as well as the other relevant restrictions on character strings must be maintained. A single character, for example in the form of a numeric character reference, may correspond to one or two 16-bit units.
ancestor
An ancestor node of any node A is any node above A in a tree model of a document, where "above" means "toward the root."
API
An API is an Application Programming Interface, a set of functions or methods used to access some functionality.
child
A child is an immediate descendant node of a node.
client application
A [client] application is any software that uses the Document Object Model programming interfaces provided by the hosting implementation to accomplish useful work. Some examples of client applications are scripts within an HTML or XML document.
COM
COM is Microsoft's Component Object Model [COM], a technology for building applications from binary software components.
convenience
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.
data model
A data model is a collection of descriptions of data structures and their contained fields, together with the operations or functions that manipulate them.
descendant
A descendant node of any node A is any node below A in a tree model of a document, where "below" means "away from the root."
document element
There is only one document element in a Document. This element node is a child of the Document node. See Well-Formed XML Documents in XML [XML 1.0].
document order
There is an ordering, document order, defined on all the nodes in the document corresponding to the order in which the first character of the XML representation of each node occurs in the XML representation of the document after expansion of general entities. Thus, the document element node will be the first node. Element nodes occur before their children. Thus, document order orders element nodes in order of the occurrence of their start-tag in the XML (after expansion of entities). The attribute nodes of an element occur after the element and before its children. The relative order of attribute nodes is implementation-dependent.
ECMAScript
The programming language defined by the ECMA-262 standard [ECMAScript]. As stated in the standard, the originating technology for ECMAScript was JavaScript [JavaScript]. Note that in the ECMAScript binding, the word "property" is used in the same sense as the IDL term "attribute."
element
Each document contains one or more elements, the boundaries of which are either delimited by start-tags and end-tags, or, for empty elements by an empty-element tag. Each element has a type, identified by name, and may have a set of attributes. Each attribute has a name and a value. See Logical Structures in XML [XML 1.0].
information item
An information item is an abstract representation of some component of an XML document. See the [XML Information set] for details.
logically-adjacent text nodes
Logically-adjacent text nodes are Text or CDataSection nodes that may be visited sequentially in document order without entering, exiting, or passing over Element, Comment, or ProcessingInstruction nodes.
hosting implementation
A [hosting] implementation is a software module that provides an implementation of the DOM interfaces so that a client application can use them. Some examples of hosting implementations are browsers, editors and document repositories.
HTML
The HyperText Markup Language (HTML) is a simple markup language used to create hypertext documents that are portable from one platform to another. HTML documents are SGML documents with generic semantics that are appropriate for representing information from a wide range of applications. [HTML 4.01]
inheritance
In object-oriented programming, the ability to create new classes (or interfaces) that contain all the methods and properties of another class (or interface), plus additional methods and properties. If class (or interface) D inherits from class (or interface) B, then D is said to be derived from B. B is said to be a base class (or interface) for D. Some programming languages allow for multiple inheritance, that is, inheritance from more than one class or interface.
interface
An interface is a declaration of a set of methods with no information given about their implementation. In object systems that support interfaces and inheritance, interfaces can usually inherit from one another.
language binding
A programming language binding for an IDL specification is an implementation of the interfaces in the specification for the given language. For example, a Java language binding for the Document Object Model IDL specification would implement the concrete Java classes that provide the functionality exposed by the interfaces.
local name
A local name is the local part of a qualified name. This is called the local part in Namespaces in XML [XML Namespaces].
method
A method is an operation or function that is associated with an object and is allowed to manipulate the object's data.
model
A model is the actual data representation for the information at hand. Examples are the structural model and the style model representing the parse structure and the style information associated with a document. The model might be a tree, or a directed graph, or something else.
namespace prefix
A namespace prefix is a string that associates an element or attribute name with a namespace URI in XML. See namespace prefix in Namespaces in XML [XML Namespaces].
namespace URI
A namespace URI is a URI that identifies an XML namespace. This is called the namespace name in Namespaces in XML [XML Namespaces].
object model
An object model is a collection of descriptions of classes or interfaces, together with their member data, member functions, and class-static operations.
parent
A parent is an immediate ancestor node of a node.
partially valid
A node in a DOM tree is partially valid if it is well formed (this part is for comments and processing instructions) and its immediate children are those expected by the content model. The node may be missing trailing required children yet still be considered partially valid.
qualified name
A qualified name is the name of an element or attribute defined as the concatenation of a local name (as defined in this specification), optionally preceded by a namespace prefix and colon character. See Qualified Names in Namespaces in XML [XML Namespaces].
read only node
A read only node is a node that is immutable. This means its list of children, its content, and its attributes, when it is an element, cannot be changed in any way. However, a read only node can possibly be moved, when it is not itself contained in a read only node.
root node
The root node is a node that is not a child of any other node. All other nodes are children or other descendants of the root node.
sibling
Two nodes are siblings if they have the same parent node.
string comparison
When string matching is required, it is to occur as though the comparison was between 2 sequences of code points from [Unicode 2.0].
token
An information item such as an XML Name which has been tokenized.
tokenized
The description given to various information items (for example, attribute values of various types, but not including the StringType CDATA) after having been processed by the XML processor. The process includes stripping leading and trailing white space, and replacing multiple space characters by one. See the definition of tokenized type.
well-formed document
A document is well-formed if it is tag valid and entities are limited to single elements (i.e., single sub-trees).
XML
Extensible Markup Language (XML) is an extremely simple dialect of SGML which is completely described in this document. The goal is to enable generic SGML to be served, received, and processed on the Web in the way that is now possible with HTML. XML has been designed for ease of implementation and for interoperability with both SGML and HTML. [XML 1.0]
XML name
See XML name in the XML specification ([XML 1.0]).
XML namespace
An XML namespace is a collection of names, identified by a URI reference [IETF RFC 2396], which are used in XML documents as element types and attribute names. [XML Namespaces]