 Telephone call with several participants |
A conference call (sometimes called an audio teleconference or ATC) is a telephone call in which several people share a telephone line at the same time. The conference call may be designed to allow the called party to participate during the call or set up so that the called party merely listens into the call and cannot speak.
The more limited three-way calling is available (usually at an extra charge) on home or office phone lines. For a three-way call, a normal point to point phone call is established between two parties. Then one of the parties tells the other party that they will add a third party. This party then presses the hook flash button (or recall button), and immediately dials the third party. While it is ringing, this party presses the flash/recall again to connect the three parties together. This option allows callers to add a second outgoing call to an already connected call. Three-way calling does not require any additional conference server and all mixing is handled within the endpoints, as there is no need to create separate mixes for each party or prioritise speakers when there are only three parties.