The IBM 3730 is a word-processing variant of the 3790, announced in the late 1970s.[6] It used 3790 hardware but its software made it a dedicated shared-logic word-processing system which could support a dozen or more word-processing IBM 3732 terminals, which were derived from the IBM 3270 family of terminals. Defunct IBM 3777 terminals which had been returned by customers were re-engineered and equipped with a specialized word-processing keyboard, and shipped back to other customers as part of the 3730 word processing system. The 3730 could be connected using Systems Network Architecture to a central mainframe running IBM DISOSS which was a centralized document exchange software running on CICS.