Complex sentence: In 1989 the firm launched MultiPlatter, a system for networking CD-ROMs across local area networks, followed in 1991 by ERL (the electronic reference library), a system for providing hard disk access to its databases via the DXP protocol.
Split into simpler sentences: In 1989 the firm launched MultiPlatter, a system for networking CD-ROMs across local area network. In 1991 it introduced searching the data held at the company's site by ERL (the electronic reference library), a system for providing hard disk access to its databases via the DXP protocol.