IRC in the context of "Online community"

Mozilla Thunderbird is a free and open-source personal information manager primarily used as an e-mail client with a calendar and contactbook, as well as an RSS feed reader, chat client (IRC/XMPP/Matrix), and news client. Operated by MZLA Technologies Corporation, a subsidiary of the Mozilla Foundation, Thunderbird is an independent, community-driven project that is managed and overseen by the Thunderbird Council, which is elected by the Thunderbird community. As a cross-platform application, Thunderbird is available for Windows, macOS, FreeBSD, Android, and Linux. The project strategy was originally modeled after that of Mozilla's Firefox, and Thunderbird is an interface built on top of that Web browser.

In computer networking, a private message (PM), or direct message (DM), refers to a private communication, often text-based, sent or received by a user of a private communication channel on any given platform. Unlike public posts, PMs are only viewable by the participants. Long a function present on IRCs and Internet forums, private channels for PMs have also been prevalent features on instant messaging (IM) and on social media networks. It may be either synchronous (e.g. on an IM) or asynchronous (e.g. on an Internet forum).

The term private message (PM) originated as a feature on internet forums, while the term direct message (DM) originated as a feature on Twitter. Due to the popularity of the latter service, DM has since been appropriated by other platforms, such as Instagram, and is often genericized in popular usage.

A discussion group is a group of individuals, typically who share a similar interest, who gather either formally or informally to discuss ideas, solve problems, or make comments. Common methods of conversing including meeting in person, conducting conference calls, using text messaging, or using a website such as an Internet forum. People respond, add comments, and make posts on such forums, as well as on established mailing lists, in news groups, or in IRC channels. Other group members could choose to respond by posting text or image.