How did Local Area Networks come about?

These are available in Code Division Multiple Access(CDMA), Digital Enhanced Cordless Telecommunications - DECT (TDMA/DCA) ( See ETSI 6 EN 300 765-1 V1.3.1 (2001-04) -"Digital Enhanced Cordless Telecommunications (DECT); Radio in the Local Loop (RLL) Access Profile (RAP); Part 1: Basic telephony services"), Global System for Mobile Communications(GSM), IS136 Time Division Multiple Access(TDMA) as well as analog access technologies such as Advanced Mobile Phone System(AMPS), for which there will be independent standards defining every aspect of modulation, protocols, error handling, etc.