A discussion group is an online forum for individuals to discuss various topics amongst each other. People add their comments by posting a block of text to the group. Others can then comment and respond. In the early days of the Internet, USENET was the most popular type of discussion group, but now discussions mostly take place over the World Wide Web using special server software.

This term encompasses: bulletin boards, listservs, mailing lists, newsgroups, etc.

Contrast with chatrooms.