This is an alphabetic list of defunct instant messaging platforms, showing the name, when it was discontinued and the type of client.
AIM was an instant messaging and presence computer program created by AOL, which used the proprietary OSCAR instant messaging protocol and the TOC protocol to allow registered users to communicate in real time.
ICQ New is a cross-platform instant messaging (IM) and VoIP client. The name ICQ derives from the English phrase "I Seek You". Originally developed by the Israeli company Mirabilis in 1996, the client was bought by AOL in 1998, and then by Mail.Ru Group in 2010.
Instant messaging (IM) technology is a type of online chat allowing immediate transmission of messages over the Internet or another computer network. Messages are typically transmitted between two or more parties, when each user inputs text and triggers a transmission to the recipient(s), who are all connected on a common network. It differs from email in that conversations over instant messaging happen in real-time. Most modern IM applications use push technology and also add other features such as emojis, file transfer, chatbots, voice over IP, or video chat capabilities.
Trillian is a proprietary multiprotocol instant messaging application created by Cerulean Studios. It is currently available for Microsoft Windows, Mac OS X, Linux, Android, iOS, BlackBerry OS, and the Web. It can connect to multiple IM services, such as AIM, Bonjour, Facebook Messenger, Google Talk (Hangouts), IRC, XMPP (Jabber), VZ, and Yahoo! Messenger networks; as well as social networking sites, such as Facebook, Foursquare, LinkedIn, and Twitter; and email services, such as POP3 and IMAP.
Messenger was an instant messaging and presence system developed by Microsoft in 1999 for use with its MSN Messenger software. It was used by instant messaging clients including Windows 8, Windows Live Messenger, Microsoft Messenger for Mac, Outlook.com and Xbox Live. Third-party clients also connected to the service. It communicated using the Microsoft Notification Protocol, a proprietary instant messaging protocol. The service allowed anyone with a Microsoft account to sign in and communicate in real time with other people who were signed in as well.
Pidgin is a free and open-source multi-platform instant messaging client, based on a library named libpurple that has support for many instant messaging protocols, allowing the user to simultaneously log in to various services from a single application, with a single interface for both popular and obsolete protocols, thus avoiding the hassle of having to deal with new software for each device and protocol.
Extensible Messaging and Presence Protocol is an open communication protocol designed for instant messaging (IM), presence information, and contact list maintenance. Based on XML, it enables the near-real-time exchange of structured data between two or more network entities. Designed to be extensible, the protocol offers a multitude of applications beyond traditional IM in the broader realm of message-oriented middleware, including signalling for VoIP, video, file transfer, gaming and other uses.
Yahoo! Messenger was an advertisement-supported instant messaging client and associated protocol provided by Yahoo!. Yahoo! Messenger was provided free of charge and could be downloaded and used with a generic "Yahoo ID" which also allowed access to other Yahoo! services, such as Yahoo! Mail. The service also offered VoIP, file transfers, webcam hosting, a text messaging service, and chat rooms in various categories.
Kopete is a multi-protocol, free software instant messaging client released as part of the KDE Software Compilation. Although it can run in numerous environments, it was designed for and integrates with the KDE Plasma Workspaces. Kopete was started because ICQ blocked Licq from their network in 2001. According to the original author, Duncan Mac-Vicar Prett, the name comes from the Chilean Spanish word copete, meaning "a drink with your friends". Kopete has been nominated for multiple awards. The designated successor is KDE Telepathy from the KDE RTCC Initiative.
Google Talk was an instant messaging service that provided both text and voice communication. The instant messaging service was variously referred to colloquially as Gchat, Gtalk, or Gmessage among its users.
Skype for Business Server is real-time communications server software that provides the infrastructure for enterprise instant messaging, presence, VoIP, ad hoc and structured conferences and PSTN connectivity through a third-party gateway or SIP trunk. These features are available within an organization, between organizations and with external users on the public internet or standard phones.
Skype for Business is an enterprise software application for instant messaging and videotelephony developed by Microsoft as part of the Microsoft 365 suite. It is designed for use with the on-premises Skype for Business Server software, and a software as a service version offered as part of 365. It supports text, audio, and video chat, and integrates with Microsoft 365 components such as Exchange and SharePoint.
Microsoft Notification Protocol is an instant messaging protocol developed by Microsoft for use by the Microsoft Messenger service and the instant messaging clients that connect to it, such as Skype since 2014, and the earlier Windows Live Messenger, MSN Messenger, Windows Messenger, and Microsoft Messenger for Mac. Third-party clients such as Pidgin and Trillian can also communicate using the protocol. MSNP was first used in a publicly available product with the first release of MSN Messenger in 1999.
Meebo was an instant messaging and social networking service provider. It was founded in September 2005 by Sandy Jen, Seth Sternberg, and Elaine Wherry, and was based in Mountain View, California. Initially the company offered a web-based instant messenger service, extending its offer in more general online chat and even social networking directions. In June 2012, Google acquired Meebo to merge the company's staff with the Google+ developers team.
eBuddy is a privately held Dutch software company that offers instant messaging services. As of 2011, eBuddy reported 100 million downloads. The company's flagship service is XMS, a proprietary cross-platform instant messaging service. After some changes of ownership, the company is now again owned by its original founders, Onno Bakker and Jan-Joost Rueb.
Outlook.com, formerly Hotmail, is a free personal email service offered by Microsoft. This includes a webmail interface featuring mail, calendaring, contacts, and tasks services. Outlook can also be accessed via email clients using the IMAP or POP protocols.
MSN Messenger, later rebranded as Windows Live Messenger, was a cross-platform instant-messaging client developed by Microsoft. It connected to the now-discontinued Microsoft Messenger service and, in later versions, was compatible with Yahoo! Messenger and Facebook Messenger. The service was discontinued in 2013 and was replaced by Skype.
aMSN was a free Windows Live Messenger clone. aMSN attempted to emulate the look and feel of Windows Live Messenger, and supported many of its features. It had been downloaded approximately 40 million times as of January 2011, making it the 21st most downloaded project on SourceForge.
MSN Dial-up is an Internet service provider operated by Microsoft in the United States and formerly also in several other countries. Originally named The Microsoft Network, it debuted as a proprietary online service on August 24, 1995, to coincide with the release of Windows 95. In 1996 and 1997, a revised web-based version of the ISP was an early experiment at interactive multimedia content on the Internet.
Comparison of user features of messaging platforms refers to a comparison of all the various user features of various electronic instant messaging platforms. This includes a wide variety of resources; it includes standalone apps, platforms within websites, computer software, and various internal functions available on specific devices, such as iMessage for iPhones.