Providing online interactive bulletin boards for transmission of messages among computer users concerning classified listings and listings for advertisements, announcements, events, activities, opportunities, and information on a wide variety of topics of general interest to the public; providing on-line forums and discussion groups for transmission of messages among computer users concerning health, family, arts, politics, leisure, romance, work, and information on a wide variety of topics of general interest to the public; electronic mail services; electronic mail subscription services; and electronic transmission of messages, data and images