1. An early, barely-functional version of a program which can be used for demonstration purposes as long as the operator uses *exactly* the right commands and skirts its numerous bugs, deficiencies, and unimplemented portions.
2. A special version of a finished program (frequently with some features crippled) which is distributed at little or no cost to the user for enticement purposes. See crippleware.
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Nearby terms: demon « Demon Internet Ltd. « DeMorgan's theorem « demo version » Denis Howe » Dennis Ritchie » denotational semantics