Telcos then extended their market by providing conference calling services to home consumers for an added fee.  For some, it made sense to be able to bring a family or group with common interests together easily, usually to plan some physical event.
With the expansion of the internet, and in particular, the increasing availability and decreasing pricing for high speed internet access, conference calling has expanded far beyond its original uses.

For business, it remains a vital tool and has, actually, become far more useful as prices fall and the ease of use increases.  Real time audio/video conferencing is already in use (and in some organizations has been for quite some time).  As the cost of bandwidth decreases and the technology underlying audio-video transmission over networks improves, true real-time video conferencing will increase dramatically.

With the growing sophistication of the typical surfer and the expansion of internet marketing, audio and video have become hot items.  Within the internet marketing community, conference calls - usually known as teleseminars, have become a standard feature.  Offering the opportunity to reach a large group of interested prospects in a relatively simple and  inexpensive format, teleseminars also offer the marketer an opportunity to create an instant product.  A recording of a teleseminar can either be sold as a stand-alone product or used as a marketing tool for back-end products.

Marketers are using both free and paid teleseminars. Generally there is a higher level of injected sales content in free teleseminars, but it does vary a great deal.

Solutions available now range from the rather expensive to essentially free.  Your choice is going to depend on exactly what level of service you require. There are a number of providers which offer an introductory pricing scheme (I've seen it as low as a $1 for the first month), which gives you the opportunity to see firsthand how their service works at a very modest cost.  You do need to make sure you understand just how your users will access the conference.  Solutions which use telephone call-ins are generally more restrictive and/or expensive than those utilizing an internet connection or VoIP softphone connections.

True real-time audio/video conferencing hasn't arrived yet for most.  The bandwidth requirements remain excessive and the quality of the video, in particular, is fairly low.  If you ever done live chat with audio and a web camera, you've seen the limitations.

Most online presentations which involve both audio and video generally use static images which change either rarely or slowly, such as charts, website images, topic outlines and so on. This can be extremely useful for teleseminars, of course, because it makes it easier to demonstrate certain points and provides a visual as well as an audio focus for participants.

The combination of audio and visual elements is particularly useful in training situations where one can reinforce the other.  Plus, you have the advantage of reaching those who learn better through visual means, as well as those partial to audio.

For those of you doing eCommerce the evolved conference call can be an incredible tool.  Consider how much impact regular teleseminars about your area of expertise could have on future sales. You can provide buyers with instructional teleseminars. You can introduce new products. And in each instance you'll be generating recordings which you can either sell or make available on your sites, or use as added viral marketing tools.

With the increasing sophistication and usability of the tools for conference calling, the possibilities are virtually unlimited and well within the reach of every entrepreneur.  You'll be hard pressed to find another tool that offers you the impact and potential of the conference call.