A Web page with dynamic content, or one where the content is frequently changed. On the fly is the opposite of a static or hardwired page whose content seldom changes.

To write on the fly means to write directly from source data to CD data without first writing a disc image.

An expression used to describe the process by which information is generated or compiled, formatted and transmitted on demand rather than from a static data source, e.g., the generation of a set of retrieved data customized according to the user's preferences; or the conversion upon request of SGML-encoded material to HTML for presentation to a user who lacks an SGML viewer.

"On the fly" describes activities that develop or occur dynamically rather than as the result of something that is statically predefined. For example, the content of a page that is sent to you from a Web site can be developed (and varied) "on the fly" based on dynamic factors such as the time of day, what pages the user has looked at previously, and specific user input. The Web server calls an application program to produce the "on-the-fly" page that is to be returned. There are several techniques for "on-the-fly" page development, including the Server-side include, the use of cookie , and Active Server Page.

To write directly to disc without first creating a disc image.

adv. Doing a task or process as needed without suspending or disturbing normal operations. For example, it is often said that an HTML document can be edited on the fly because its content can be revised without the need to completely shut down or recreate the Web site on which it resides. See also HTML document, Web site.

In colloquial use, on the fly means in a hurry, generally involving haste or carelessness.