Defined by Gene Amdahl after he left IBM to found his own company: “FUD is the fear, uncertainty, and doubt that IBM sales people instill in the minds of potential customers who might be considering [Amdahl] products.” The idea, of course, was to persuade them to go with safe IBM gear rather than with competitors' equipment. This implicit coercion was traditionally accomplished by promising that Good Things would happen to people who stuck with IBM, but Dark Shadows loomed over the future of competitors' equipment or software. See IBM. After 1990 the term FUD was associated increasingly frequently with Microsoft, and has become generalized to refer to any kind of disinformation used as a competitive weapon.

[In 2003, SCO sued IBM in an action which, among other things, alleged SCO's proprietary control of Linux. The SCO suit rapidly became infamous for the number and magnitude of falsehoods alleged in SCO's filings. In October 2003, SCO's lawyers filed a memorandum in which they actually had the temerity to link to the web version of this entry in furtherance of their claims. Whilst we appreciate the compliment of being treated as an authority, we can return it only by observing that SCO has become a nest of liars and thieves compared to which IBM at its historic worst looked positively angelic. Any judge or law clerk reading this should surf through to my collected resources on this topic for the appalling details.—ESR]