A conference call is a telephone call in which more than one person is listening with the permission of the calling party. The conference call can be designed to permit the called person to participate in the call or just listen without speaking to the person who is calling. This type of conference call is also sometimes termed as an audio tele-conference (ATC). This facility is widely used now in business as a way of reducing travel expenses and increasing productivity by eliminating the need to go out of office for routine meetings.

How Does it Work?
In a conference call, the person who is making the call may add the various participants to the call, but participants can also log on to the call themselves by dialing a particular number that connects to a conference bridge. This is a kind of equipment which links various telephone lines and is usually maintained by the conference call service provider. Alternately, the conference call can be managed in-house if the PBX offers that functionality. The provider gives the numbers and PIN codes that the participants have to dial in order to access the conference call.

Business Applications of Conference Calls
Business uses for conference calls are varied, ranging from client meetings and sales presentations to project updates and employee training sessions. Nearly all public corporations in the United States use a conference call to report their quarterly results. Conference calls are often made in tandem with web conferences, where presentations and other aspects of company operations are communicated through the Internet, through a visual presentation such as a PowerPoint. People can then view the content, and the presenter can clarify all details.

Social Networking
A conference call is now part of podcasting and social networks, where new kinds of interactive methods are emerging. More people can access live streaming or broadcasting of conference calls without any linking to the bridge. The organizers provide a dial-in number with the audio, to permit the listeners to call and interact if they wish to do so.

Entertainment
Social contact and entertainment objectives are also being served, with the conference call being used for group calls or a party line. Here, people dial a particular number and access a telephone conversation with others. This kind of call can be a way to interact with new people and thereby make friends and social contacts.

Types of Conference Calls
Conference calls are often offered by third party providers at flat rates, where the users can have unlimited access to a conference bridge for a payment at a fixed monthly rate. Then there are prepaid type where the users can buy the service online and conduct the calls on a pay-as-you-go basis. These calls permit the users to make such calls through the normal telephone lines or cell phones or the computer and no additional hardware has to be bought for the facility. Some services even permit conference calls from any country which has the necessary telephone access.

While third party conference call services have become very popular, larger companies may still wish to host their own if they have the appropriate on-premises equipment. Many of the more advanced PBXes, especially IP PBXes, deliver the ability to host conference calls. Doing so may require some special training for the operator.