Note: Many topics at this site are reduced versions of the text in "The Encyclopedia of Networking and Telecommunications." Search results will not be as extensive as a search of the book's CD-ROM.

A compound document is like a container that holds text, graphics, and multimedia video and sound objects. Early on, Microsoft Windows and the Macintosh used this technology, which allows users to create documents with a word processor, spreadsheet program, or other program, and embed or link objects in the documents. An electronic mail message with an attachment such as a graphic is also a compound document.

Today, a Web page is the best example of a compound document. It holds text and individual objects like pictures, sounds, videos, Java applets, and ActiveX controls.

The original purpose of compound documents was to provide a single place where users could create a document that contained all the elements related to that document. When you save a compound document, you save all the text and objects under the same filename even though objects remain as separate files for editing or inclusion in other documents.

In the case of a Web server HTML document, a simple link or hyperlink to external objects is all that is needed to display those objects in documents. For example, an image of a company's logo can be stored on a Web server and then opened for display on any Web page. If the logo is called LOGO.GIF, a tag is placed in an HTML document to display the logo. The LOGO.GIF image file can be altered at any time. The next time a Web page is opened by a user, the new logo is displayed because the Web page simply searches for LOGO.GIF and displays it.

An active document contains objects or components that are manually or automatically updated from a source called the server. For example, if a compound document contains a link to a graphic image that has been updated by someone else, the graphic in the compound document is updated the next time the document is opened. This concept has been extended to the Internet and the Web. Java and ActiveX are now the primary tools for creating active documents that contain applets and components that perform a variety of actions or tasks.

One of the advantages of this technology is that the document signals the source when it needs to have its objects updated. This frees the server from having to continuously provide updates when it may be unnecessary. When an active document is opened, that is when updates can occur, but if necessary, an active document can be continuously updated. This is the case where information is updated in real time and the server broadcasts information on a continuous basis. See "Webcasting" for more information on this technology.

On the World Wide Web, Web pages are active documents that are dynamically updated, often in real time. Note that Web pages may be either static or dynamic. A static page does not change except when the Webmaster makes changes to it. Everyone who accesses the page sees the same information. Dynamic Web pages, on the other hand, are created on-the-fly, based on information the user typed into a form or, based on other information such as the current time, date, and other information. For example, you may enter stock symbols into a form, and then get a personalized Web page back from the server that details the current value of your stock holdings.

Active documents are discussed in a document written by Sandy Ressler called "Perspectives on Electronic Publishing." The document is located at the U.S. government's NIST (National Institute of Standards) Web site. See the Web site listed on the related entries page. It provides an example of a pie chart in a document that is automatically updated as data in a spreadsheet changes. In another case, a change to a document may initiate an electronic mail message that is sent to the author of the document or someone else responsible for its contents. The mechanisms that allow these updates are as follows:

• OLE (Object Linking and Embedding) in the Windows environment


• The Publish and Subscribe facility in the Macintosh environment


• RPC (remote procedure calls) on UNIX and Windows systems


• Component Software Technologies such as Java and ActiveX

Refer to the related entries page for links to these topics

Copyright (c) 2001 Tom Sheldon and Big Sur Multimedia.
All rights reserved under Pan American and International copyright conventions.