Free conference calls connect businesses, organizations, and personal groups alike. Some of these services allow moderator functions, such as muting callers, question-and-answer mode, and secure conference PIN codes for moderators and conference participants. Free teleconferences take place all around the world and can have hundreds of callers. Some free conference calls use traditional telephone lines and equipment, while others add in Voice Over Internet Protocol (VOIP) technology to lower company costs and expand accessibility to international users.Many teleconference services also require callers to dial a conference code and PIN, thus increasing the security of the conference call. It is harder for outsiders to eavesdrop on private calls if they do not know the conference...