Symbolics was a start-up spinoff of the MIT AI Lab founded in 1980, whose goal was to build and sell LISP machines. It had a moderately successful run, but after internal dissension and some poor business decisions, it went bankrupt in 1996.
During its lifetime, Symbolics produced 4 generations of hardware:
- the LM-2, a slightly improved and repackaged CADR, intended as an interim product
- the L-Machines (models 3600, 3670, 3640, 3675 and 3645); built out of stock TTL
- the G-machines (models 3650, 3620, 3630, 3619); built from custom gate arrays
- the I-machines (standalone: XL400, XL1200, XL1201 and NXP1000; Sun: UX400, UX1200; Macintosh: MacIvory I, II, III); custom ICs
Technically, what doomed specialized LISP machines was the fact that stock microprocessors sped up to such a degree that even the specialized support available in the low-production-volume custom CPU of the LISP machine (tagged data types; garbage collection) left them unable to keep up.