/V-I/, *not* /vi/ and *never* /siks/
[from Visual Interface]
n. A screen editor crufted together by Bill Joy for an early BSD version. Became the de facto standard UNIX editor and a nearly undisputed hacker favorite until the rise of EMACS after about 1984. Tends to frustrate new users no end, as it will neither take commands while expecting input text nor vice versa, and the default setup provides no indication of which mode one is in (one correspondent accordingly reports that he has often heard the editor's name pronounced /vi:l/). Nevertheless it is still widely used (about half the respondents in a 1991 USENET poll preferred it), and even EMACS fans often resort to it as a mail editor and for small editing jobs (mainly because it starts up faster than bulky EMACS).
See holy wars.