Glossary

DID (direct inward dialling)

A DID is a phone number that routes an outside caller to a specific destination without going through a switchboard.

The term comes from the era when a company had one main line and an operator transferred you. Direct inward dialling gave individual extensions their own external numbers, so callers could reach a person directly.

Today it is used loosely to mean any number you can point somewhere. For a voice agent the useful property is that DIDs are cheap and plentiful, so different numbers can route to different agents — a support line, a bookings line and an out-of-hours line can each behave differently while belonging to the same business.

Related

  • SIP trunk — A SIP trunk is a connection that carries phone calls over the internet between your telephony provider and another system.
  • BYOC (bring your own carrier) — BYOC means connecting your own telephony account to a platform rather than buying numbers from that platform.
  • IVR (interactive voice response) — An IVR is an automated phone menu that routes callers based on keypresses or short spoken commands.