few words, for example, habeas corpus for habeas corpus ad subjiciendum ("may you have the person to be subjected [to examination]") which are itself the key words of a much longer writ. Many word processors propose the first few words of a document as a default file name, assuming that the incipit may correspond to the intended title of the document. The space-filling, or place-holding, text lorem ipsum is known as such from its incipit. Occasionally, incipits have been used for humorous effect, such as in the Alan Plater-penned television series The Beiderbecke Affair and its sequels, in which each episode is named for the first words spoken in the episode (leading to episode titles such as "What I don't understand is this..." and "Um...I know what you're thinking"). In music Musical incipits are printed in standard music notation. They typically feature the first few bars of a piece, often with the most prominent musical material written on a single staff (the examples given at right show both the single-staff and full-score incipit variants). Incipits are especially useful in music because they can call to mind the reader's own musical memory of the work where a printed title would fail to do so. Musical incipits appear both in catalogs of music and in the tables of contents of volumes that include multiple works. In choral music, sacred or secular pieces from before the 20th century were often titled with the incipit text. For instance, the proper of the Catholic Mass and the Latin transcriptions of the biblical psalms used as prayers during services are always titled with the first word or words of the text. Protestant hymns of the eighteenth and nineteenth centuries are also traditionally titled with an incipit. In computer science In computer science, long strings of characters may be referred to by their incipits, particularly encryption keys or product keys. Notable examples include FCKGW (used by Windows XP) and 09 F9 (used by Advanced Access Content System). See also Epigraph Exordium (rhetoric) Preface Prologue Rubrication Notes References Other sources Barreau, Deborah K.; Nardi, Bonnie. "Finding and Reminding: File Organization From the desktop". SigChi Bulletin. July 1995. Vol. 27. No. 3. pp. 39–43 Casson, Lionel. Libraries in the Ancient World. New Haven, Connecticut: Yale University Press, 2001. . . Malone, Thomas W. "How do people organize their desks? Implications for the design of Office Information Systems". ACM Transactions