Direct Inward Dialing (DID)
Direct Inward Dialing (DID) is a block of telephone numbers for calling into a company's PBX (Private Branch Exchange) system.
Using DID, you can offer your customers individual phone numbers for each person or workstation within your company without requiring a physical line into the PBX for each possible connection. A DID system can be used for fax and voicemail as well as for live voice connections. Compared to regular PBX service, DID saves the cost of a switchboard operator, calls go through faster, and callers feel they are calling a person rather than a company.

