Hypertext Terms

This is a glossary of terms used within the WWW project. In most cases, their use corresponds to conventional use in hypertext circles.

Anchor An area within a the content of a node which is the source or destination of a link. The anchor may be the whole of the node content. Typically, clicking a mouse on an anchor area causes the link to be followed, leaving the anchor at the opposite end of the link displayed. Anchors tend to be highlighted in a special way (always, or when the mouse is over them), or represented by a special symbol. An anchor may, and often does, correspond to the whole node. (also sometimes known as "span", "region", "button", or "extent").

Annotation The linking of a new commentary node to an existing node. If readers can annotate nodes, then they can immediately provide feedback if the information is misleading, out of date or plain wrong. Thus the quality of the information in the web can be improved.

Authoring A term for the process of writing a document. "Authoring" seems to have come into use in order to emphasise that document production involved more than just writing.

Back link A link in one direction implied from the existence of an explicit limk in the other direction.

Browser A program which allows a person to read hypertext. The browser gives some means of viewing the contents of nodes, and of navigating from one node to another.

Button An anchor which is the source of a link. Often, but not always, represented on screen to look like a push-button.

Card An alternative term for a node in a system (e.g. HyperCard, Notecards) in which the node size is limited to a single page of a limited size.

Client A program which requests services of another program. Normally, the browser is a client of a data server.

Cyberspace This is the "electronic" world as perceived on a computer screen, the term is often used in opposition to the "real" world. With Web-extensions like VRML and the Cyberspace Protocol, Virtual Reality will one day come to your home computer.

Database We have used this vaguely as a term for a collection of nodes. We imagine management information for one of these being kept in one place and all being accessible by the same server. Links outside this are "external", and those inside are "internal". We do not imply anything about how the information shored be stored.

Daemon A program which runs independently of, for example the browser. Daemons may perform various management tasks such as building indexes, overviews, and back-links. Under unix, "daemon" is used for " server ", because servers normally run independently.

Document A term for a node on some systems (eg Intermedia). Sometimes used by others as a term for a collection of nodes on related topics, possible stored or distributed as one. The prefered term in W3 documentation.

Domain We have used this specifically for a unit of protection. It could possibly correspond to a database, and in that case would be a better (less vague) term for it.

External A link to a node in a different database. See Database

Host A computer on a network. We use this term rather than the term " node " which is often used for a document in a hypertext web.

Hypermedia MultiMedia Hypertext. HyperMedia and HyperText tend to be used loosely in place of each other. Media other than text typically include graphics, sound, and video.

Hypertext Text which is not constrained to be linear.

Index Something which points at other data; a server facility which provides pointers to particular data as a function of a query; a table of contents of a book in hypertext form.

Internal A link to a node in the same database. See database.

Link A relationship between two anchors, stored in the same or different database. See "Internal" and "External".

Navigation The process of moving from one node to another through the hypertext web. This is normally done by following links. Various features of a particular browser may make this easier. These include keeping a history of where the user has been, and drawing diagrams of links between nearby nodes.

Node A unit of information. Also known as a frame (KMS), card (Hypercard, Notecards). Used with this special meaning in hypertext circles: do not confuse with "node" meaning "network host". For user's benefits, we use the term " document " as this is the nearest term outside the hypertext world.

Protection The prevention of unauthorized users from reading, or writing, a particular piece of data. Also known as "authentication", "access control", etc.

Path An ordered set of nodes or anchors which represent a sequence in which a web can be read. A path may represent the sequence a reader actually used, or may be a sequence recommened to the reader by the author.

Reader We have used this term for the person who browses, to distinguish him/her from the program ( browser ) which (s)he uses.

Server A program which provides a service to another, known as the client. In a hypertext system, a server will provide hypertext information to a browser. See also: daemon.

Tracing The automatic finding of nodes by automatic navigation. Examples might be finding all nodes dependent on another node, all people interested in a given node, all modules which use a given module. Another example is a trace starting with more than one node, such as to find a node in common between two groups, or path linking two nodes.

Topology The allowable connectivity between nodes, anchors and links: for example, 1-1 or many-1 mappings.

Versioning The storage and management of previous versions of a piece of information, for security, diagnostics, and interest. This is important when many users are allowed to edit the same material.

VRML Virtual Reality Modeling Language. The term "VRML" had been coined by Dave Ragget at the 1st WWW Conference in Geneva, May 1994. VRML is proposed as a logical markup format for non-proprietary platform independent VR.

Web A set of nodes interconnected by links. Often, the set of all the nodes which are interconnected. See also Topology.