Topic summary
PABX
Extracted from the Wikipedia article Business telephone system.
History
The term PBX originated when switchboard operators managed company switchboards manually using cord circuits. As automated electromechanical switches and later electronic switching systems gradually replaced the manual systems, the terms private automatic branch exchange (PABX) and private manual branch exchange (PMBX) differentiated them. Solid-state digital systems were sometimes referred to as electronic private automatic branch exchanges (EPABX). As of 2021, the term PBX is by far the most widely recognized. The abbreviation now applies to all types of complex, in-house telephony switching systems.