Conferencing software has been maturing for over 20 years now, and there is plenty of it available on a variety of platforms. But Web-based conferencing is still quite young. The first examples appeared only about a year ago. On the whole, Web conferencing hasn't yet caught up with conferencing software for other platforms. Last year I contributed a chapter on this subject for the book "World Wide Web Unleashed," and in April I updated it for a 2nd edition. The full text of the chapter is available at: http://freenet.msp.mn.us:8000/~drwool/webconf.htm This page also has links to all of the Web-based conferencing systems that I know of. Even though Web conferencing is still immature, just the fact that it's on the Web is an advantage that might outweigh other considerations in some cases. If you're using the Web to teach a course, and the course design involves online group discussion, naturally you would want to use the Web as the platform for discussions. As of this moment, if you want to set up a Web site that offers conferencing, there are five methods that I would say are worth considering: * WebNotes * HyperNews * Forum News Gateway * HyperMail * Roll-your-own WebNotes is by far the best, most robust, and most feature-rich Web-based conferencing software available. It's also the only commercial product in this category, and it's not cheap: it will run you somewhere between $1,500 and $15,000 depending on how many simultaneous users you want to support (the low end of that range is for 10 users.) Currently it's only available for Windows NT servers, but they are working on a Unix version. HyperNews and the Forum News Gateway are less capable, but they're free, and they might be adequate for low-volume conferencing. HyperMail is also free. It's not really a conferencing system at all, but it's sometimes used that way. It converts an archive of an e-mail discussion into HTML pages that can be browsed over the Web. In fact, this very ICDE-95 session is being mirrored on a Web site by HyperMail. In case you missed Terry's announcement, you can browse this discussion at: http://web.cs.ualberta.ca/~kannan/icde95/ The reason I say it's not really a conferencing system is that it doesn't thread messages very well. It's more oriented toward individual messages than toward topics. "Rolling-your-own" is a popular option. Someone who's good at writing CGI scripts can hack a simple conferencing system together in a few days. Of course, it will probably be missing some features that are important for serious conferencing. For example, keeping track of what each user has read is a crucial feature for any conferencing system that is going to be used heavily, but it's quite difficult to implement on the Web. There's a lot more I can say about Web-based conferencing, but I'm going to take a break here. If anyone has specific questions they would like to raise, please do, because I could take this discussion in any number of directions.