ICAD (Corporate history: ICAD, Inc., Concentra, KTI, Dassault Systemes ) was a
Knowledge-Based Engineering system that was based upon the
Lisp programming language. ICAD had an open architecture that can utilize all the power and flexibility of the underlying language. KBE, as implemented via ICAD, received a lot of attention due to the remarkable results that appeared to take little effort. ICAD allowed one example of
end-user computing that in a sense is unparalleled. Most ICAD developers were degreed engineers. Systems developed by ICAD users were non-trivial and consisted of highly complicated code. In the sense of
end-user computing, ICAD was the first to allow the power of a domain tool to be in the hands of the user at the same time being open to allow extensions as identified and defined by the domain expert or
SME.
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