An e-mail that has bounced back to the sender undelivered without having been accepted by the recipient’s mail.

Under the Health Insurance Portability and Accountability Act, healthcare entities must take specific steps to protect the privacy and personally identifiable information of their patients, including names and diagnoses. The Act is enforced by the U.S. Department of Health and Human Services’ Office of Civil Rights.

(1) Also called a page hit. The retrieval of any item, like a page or a graphic, from a Web server. For example, when a visitor calls up a Web page with four graphics, that's five hits, one for the page and four for the graphics. For this reason, hits often aren't a good indication of Web traffic. Compare with page view. (2) Any time a piece of data matches criteria you set. For example, each of the matches from a Yahoo or any other search engine search is called a hit.

The main page of a Web site. Typically, the home page serves as an index or table of contents to other documents stored at the site.

(n) A link between two applications such that changes in one affect the other. For example, some desktop publishing systems let you establish hot links between documents and databases or spreadsheets. When data in the spreadsheet changes, the corresponding charts and graphs in the document change accordingly. (v) To establish a link between two applications.

Most recent buyers on a list.

Commonly referred to as a “customer list,” a housefile is a consolidated database containing each customer’s name, address and summarised order information.

Abbreviation for Hyper Text Markup Language, which is the language used for creating documents on the World Wide Web.

An element in an electronic document that links to another place in the same document or to an entirely different document. Typically, you click on the hyperlink to follow the link. Hyperlinks are the most essential ingredient of all hypertext systems, including the World Wide Web.

A companion application, developed in the Fall of 1997 by San Francisco based software development firm Streamix Corp. as a cure for the World Wide Wait. HyperStitial technology is an application that runs alongside a browser, allowing advertisers to present full-screen ads during the delay of Web page downloads. As users wait for the content of a Web site to be displayed, or downloaded, Hyperstital "ads" are displayed in a similar manner as television commercials. Viewers are subjected to the advertisements, which are more difficult to ignore than the common banner ad.

A special type of database system, invented by Ted Nelson in the 1960s, in which objects (text, pictures, music, programs, and so on) can be creatively linked to each other. When you select an object, you can see all the other objects that are linked to it. You can move from one object to another even though they might have very different forms. For example, while reading a document about Mozart, you might click on the phrase Violin Concerto in A Major, which could display the written score or perhaps even invoke a recording of the concerto. Clicking on the name Mozart might cause various illustrations of Mozart to appear on the screen. The icons that you select to view associated objects are called Hypertext links or buttons. Hypertext systems are particularly useful for organising and browsing through large databases that consist of disparate types of information. There are several Hypertext systems available for Apple Macintosh computers and PCs that enable you to develop your own databases. Such systems are often called authoring systems. HyperCard software from Apple Computer is the most famous.