Web conferencing is made up of two key components: a voice conference call and a concurrent Web conference. Although it is possible to send and receive both over a single Internet connection, it is not recommended. A best practice is to create a voice conference call using your telephone equipment. Most of the services available today will bridge the voice and Web presentation, so that participants can control both aspects using either their phone or computer.
Let's consider potential uses and benefits:
Training - Testing and Tracking
Demonstrations - Sales
Collaboration - Meetings
Support - Desktop Sharing
There are many ways to facilitate Web conferencing. My recommendation is to do an Internet search to find a solution that fits and sign up for a free trial. Today the biggest factor in Web conferencing is usability. If it isn't simple to use, it simply won't be used.