The structure of print and on-screen documents is made explicit through headings and links. Three important concepts for understanding explicit structure are (1) the display-unit properties of each document medium, (2) the flexible relationship between explicit and implicit structure, and (3) the distinction between populated and unpopulated locations in a hierarchy. These concepts help us better understand standard print documents, structured writing, websites, help systems, and PowerPoint, as well as the potential effects of content management systems on how documents are created.

Not too long ago, publication tasks such as layout, font selection, merging of text and graphics, and copyfitting were addressed only by communication professionals. Now, programs like Pagemaker by Aldus and Ventura Publisher by Xerox make these issues just another personal computer application, like spreadsheets, calendars, and word processing. The impact of desktop publishing (DTP) is already being hotly debated, and we open this new IEEE Transactions section on communication technology with an article that has significant implications for this debate.

Consistency is the orderly treatment of a set of linked elements, and it is a necessary characteristic of polished, highly readable prose. Consistency is either “uniform” or “harmonious,” depending on whether a set of linked elements is indivisible or divisible into subsets. From the perspective of text characteristics, we can speak of semantic, syntactic, stylistic, spatial, and mechanical consistency. To deal successfully with consistency problems, technical communicators should establish patterns that are logical, evident, functional, resource efficient, and stable. Because of its importance, the concept of consistency should be more fully recognized. Indeed, consistency should be a component of any comprehensive rhetoric of technical communication.

Quotation marks and italics—two devices for giving special typographic treatment to words—are customarily used when a writer is introducing unfamiliar terms. The purpose of this as-yet-unexplained convention is to prevent the reader from experiencing a moment of apprehension in sentences in which an unfamiliar term appears several words or more before its explanation. The quotation marks or italics signal the reader that the writer knows the term is probably unfamiliar and that the term will therefore be explained. In those few instances in which unfamiliar terms are not explained, the reader infers that an explanation is not necessary for a productive reading of the text. This convention is less functional when the unfamiliar term is followed immediately by its explanation and is nonfunctional when the explanation precedes the term.