DID numbers

Direct Inward Dialing (DID) is a service of a local phone company (or local exchange carrier) that provides a block of telephone numbers for calling into a company's private branch exchange (PBX) system. DIDs are virtual numbers, which a company can offer its customer's individual phone numbers for each person/employee/ workstation within a company without requiring multiple physical phone lines. Having a DID number, a company can automatically direct a call for a given phone number to the appropriate person/employee/workstation in the company without having to go through a switchboard or operator. A DID number can process multiple simultaneous calls to the proper extensions.