a.k.a. discussion forums, online forums

What is a forum? It's an online community where users read and post topics of common interest. BTW: the plural of "forum" is "fora."

Historical perspective: Founded in early 1995 by Craig Newmark, Craig's List is a well-known forum that encourages people to post announcements in a variety of categories, such as housing wanted or available, things for sale, events, job postings, personal ads, and even stuff like, "I need a babysitter." It is a very down-to-earth approach in the sense that it's a place where people can get the word out when it comes to everyday, real-world stuff. There are now hundreds of Craig's Lists in cities around the world, giving users a way to reach out to each other in their own communities.

NetLingo Classification: Technical Terms