Instant messaging (IM) technology is a type of online chat that offers real-time text transmission over the Internet. A LAN messenger operates in a similar way over a local area network. Short messages are typically transmitted between two parties, when each user chooses to complete a thought and select "send". Some IM applications can use push technology to provide real-time text, which transmits messages character by character, as they are composed. More advanced instant messaging can add file transfer, clickable hyperlinks, Voice over IP, or video chat.
Non-IM types of chat include multicast transmission, usually referred to as "chat rooms", where participants might be anonymous or might be previously known to each other (for example collaborators on a project that is using chat to facilitate communication). Instant messaging systems tend to facilitate connections between specified known users (often using a contact list also known as a "buddy list" or "friend list"). Depending on the IM protocol, the technical architecture can be peer-to-peer (direct point-to-point transmission) or client-server (an Instant message service center retransmits messages from the sender to the communication device).
By 2010, instant messaging over the Web was already in sharp decline, in favor of messaging features on social networks. The most popular IM platforms, such as AIM, closed in 2017, and Windows Live Messenger was merged into Skype. Today, most instant messaging takes place on messaging apps which by 2014 had more users than social networks.
Instant messaging is a set of communication technologies used for text-based communication between two or more participants over the Internet or other types of networks. IM–chat happens in real-time. Of importance is that online chat and instant messaging differ from other technologies such as email due to the perceived quasi-synchrony of the communications by the users. Some systems permit messages to be sent to users not then 'logged on' (offline messages), thus removing some differences between IM and email (often done by sending the message to the associated email account).
IM allows effective and efficient communication, allowing immediate receipt of acknowledgment or reply. However IM is basically not necessarily supported by transaction control. In many cases, instant messaging includes added features which can make it even more popular. For example, users may see each other via webcams, or talk directly for free over the Internet using a microphone and headphones or loudspeakers. Many applications allow file transfers, although they are usually limited in the permissible file-size.
It is usually possible to save a text conversation for later reference. Instant messages are often logged in a local message history, making it similar to the persistent nature of emails.
Though the term dates from the 1990s, instant messaging predates the Internet, first appearing on multi-user operating systems like Compatible Time-Sharing System (CTSS) and Multiplexed Information and Computing Service (Multics) in the mid-1960s. Initially, some of these systems were used as notification systems for services like printing, but quickly were used to facilitate communication with other users logged into the same machine. As networks developed, the protocols spread with the networks. Some of these used a peer-to-peer protocol (e.g. talk, ntalk and ytalk), while others required peers to connect to a server (see talker and IRC). The Zephyr Notification Service (still in use at some institutions) was invented at MIT's Project Athena in the 1980s to allow service providers to locate and send messages to users.
Parallel to instant messaging were early online chat facilities, the earliest of which was Talkomatic (1973) on the PLATO system, which allowed 5 people to chat simultaneously on a 512x512 plasma display (5 lines of text + 1 status line per person). During the bulletin board system (BBS) phenomenon that peaked during the 1980s, some systems incorporated chat features which were similar to instant messaging; Freelancin' Roundtable was one prime example. The first such general-availability commercial online chat service (as opposed to PLATO, which was educational) was the CompuServe CB Simulator in 1980, created by CompuServe executive Alexander "Sandy" Trevor in Columbus, Ohio.
Early instant messaging programs were primarily real-time text, where characters appeared as they were typed. This includes the Unix "talk" command line program, which was popular in the 1980s and early 1990s. Some BBS chat programs (i.e. Celerity BBS) also used a similar interface. Modern implementations of real-time text also exist in instant messengers, such as AOL's Real-Time IM as an optional feature.
In the latter half of the 1980s and into the early 1990s, the Quantum Link online service for Commodore 64 computers offered user-to-user messages between concurrently connected customers, which they called "On-Line Messages" (or OLM for short), and later "FlashMail." (Quantum Link later became America Online and made AOL Instant Messenger (AIM, discussed later). While the Quantum Link client software ran on a Commodore 64, using only the Commodore's PETSCII text-graphics, the screen was visually divided into sections and OLMs would appear as a yellow bar saying "Message From:" and the name of the sender along with the message across the top of whatever the user was already doing, and presented a list of options for responding. As such, it could be considered a type of graphical user interface (GUI), albeit much more primitive than the later Unix, Windows and Macintosh based GUI IM software. OLMs were what Q-Link called "Plus Services" meaning they charged an extra per-minute fee on top of the monthly Q-Link access costs.
Modern, Internet-wide, GUI-based messaging clients as they are known today, began to take off in the mid-1990s with PowWow, ICQ, and AOL Instant Messenger. Similar functionality was offered by CU-SeeMe in 1992; though primarily an audio/video chat link, users could also send textual messages to each other. AOL later acquired Mirabilis, the authors of ICQ; a few years later ICQ (then owned by AOL) was awarded two patents for instant messaging by the U.S. patent office. Meanwhile, other companies developed their own software; (Excite, MSN, Ubique, and Yahoo!), each with its own proprietary protocol and client; users therefore had to run multiple client applications if they wished to use more than one of these networks. In 1998, IBM released IBM Lotus Sametime, a product based on technology acquired when IBM bought Haifa-based Ubique and Lexington-based Databeam.
In 2000, an open-source application and open standards-based protocol called Jabber was launched. The protocol was standardized under the name Extensible Messaging and Presence Protocol (XMPP). XMPP servers could act as gateways to other IM protocols, reducing the need to run multiple clients. Multi-protocol clients can use any of the popular IM protocols by using additional local libraries for each protocol. IBM Lotus Sametime's November 2007 release added IBM Lotus Sametime Gateway support for XMPP.
As of 2010, social networking providers often offer IM abilities. Facebook Chat is a form of instant messaging, and Twitter can be thought of as a Web 2.0 instant messaging system. Similar server-side chat features are part of most dating websites, such as OKCupid or PlentyofFish. The spread of smartphones and similar devices in the late 2000s also caused increased competition with conventional instant messaging, by making text messaging services still more ubiquitous.
Many instant messaging services offer video calling features, voice over IP and web conferencing services. Web conferencing services can integrate both video calling and instant messaging abilities. Some instant messaging companies are also offering desktop sharing, IP radio, and IPTV to the voice and video features.
The term "Instant Messenger" is a service mark of Time Warner and may not be used in software not affiliated with AOL in the United States. For this reason, in April 2007, the instant messaging client formerly named Gaim (or gaim) announced that they would be renamed "Pidgin".
In the 2010s, more people started to use messaging apps like WhatsApp, WeChat, Facebook Messenger and Line than instant messaging like AIM. For example, WhatsApp was founded in 2009, and Facebook acquired in 2014, by which time it already had half a billion users.
Each modern IM service generally provides its own client, either a separately installed piece of software, or a browser-based client. These usually only work within the same IM network, although some allow limited function with other services. Third party client software applications exist that will connect with most of the major IM services.
Standard complementary instant messaging applications offer functions like file transfer, contact list(s), the ability to hold several simultaneous conversations, etc. These may be all the functions that a small business needs, but larger organizations will require more sophisticated applications that can work together. The solution to finding applications capable of this is to use enterprise versions of instant messaging applications. These include titles like XMPP, Lotus Sametime, Microsoft Office Communicator, etc., which are often integrated with other enterprise applications such as workflow systems. These enterprise applications, or enterprise application integration (EAI), are built to certain constraints, namely storing data in a common format.
There have been several attempts to create a unified standard for instant messaging: IETF's Session Initiation Protocol (SIP) and SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE), Application Exchange (APEX), Instant Messaging and Presence Protocol (IMPP), the open XML-based Extensible Messaging and Presence Protocol (XMPP), and Open Mobile Alliance's Instant Messaging and Presence Service developed specifically for mobile devices.
However, while discussions at IETF were stalled, Reuters signed the first inter-service provider connectivity agreement in September 2003. This agreement enabled AIM, ICQ and MSN Messenger users to talk with Reuters Messaging counterparts and vice versa. Following this, Microsoft, Yahoo! and AOL agreed to a deal in which Microsoft's Live Communications Server 2005 users would also have the possibility to talk to public instant messaging users. This deal established SIP/SIMPLE as a standard for protocol interoperability and established a connectivity fee for accessing public instant messaging groups or services. Separately, on October 13, 2005, Microsoft and Yahoo! announced that by the 3rd quarter of 2006 they would interoperate using SIP/SIMPLE, which was followed, in December 2005, by the AOL and Google strategic partnership deal in which Google Talk users would be able to communicate with AIM and ICQ users provided they have an AIM account.
There are two ways to combine the many disparate protocols:
Some approaches allow organizations to deploy their own, private instant messaging network by enabling them to restrict access to the server (often with the IM network entirely behind their firewall) and administer user permissions. Other corporate messaging systems allow registered users to also connect from outside the corporation LAN, by using an encrypted, firewall-friendly, HTTPS-based protocol. Usually, a dedicated corporate IM server has several advantages, such as pre-populated contact lists, integrated authentication, and better security and privacy.
Certain networks have made changes to prevent them from being used by such multi-network IM clients. For example, Trillian had to release several revisions and patches to allow its users to access the MSN, AOL, and Yahoo! networks, after changes were made to these networks. The major IM providers usually cite the need for formal agreements, and security concerns as reasons for making these changes.
The use of proprietary protocols has meant that many instant messaging networks have been incompatible and users have been unable to reach users on other networks. This may have allowed social networking with IM-like features and text messaging an opportunity to gain market share at the expense of IM.
Users sometimes make use of internet slang or text speak to abbreviate common words or expressions to quicken conversations or reduce keystrokes. The language has become widespread, with well-known expressions such as 'lol' translated over to face-to-face language.
Some, however, attempt to be more accurate with emotional expression over IM. Real time reactions such as (chortle) (snort) (guffaw) or (eye-roll) are becoming more popular. Also there are certain standards that are being introduced into mainstream conversations including, '#' indicates the use of sarcasm in a statement and '*' which indicates a spelling mistake and/or grammatical error in the prior message, followed by a correction.
Instant messaging has proven to be similar to personal computers, email, and the World Wide Web, in that its adoption for use as a business communications medium was driven primarily by individual employees using consumer software at work, rather than by formal mandate or provisioning by corporate information technology departments. Tens of millions of the consumer IM accounts in use are being used for business purposes by employees of companies and other organizations.
In response to the demand for business-grade IM and the need to ensure security and legal compliance, a new type of instant messaging, called "Enterprise Instant Messaging" ("EIM") was created when Lotus Software launched IBM Lotus Sametime in 1998. Microsoft followed suit shortly thereafter with Microsoft Exchange Instant Messaging, later created a new platform called Microsoft Office Live Communications Server, and released Office Communications Server 2007 in October 2007. Oracle Corporation has also jumped into the market recently with its Oracle Beehive unified collaboration software. Both IBM Lotus and Microsoft have introduced federation between their EIM systems and some of the public IM networks so that employees may use one interface to both their internal EIM system and their contacts on AOL, MSN, and Yahoo. As of 2010, leading EIM platforms include IBM Lotus Sametime, Microsoft Office Communications Server, Jabber XCP and Cisco Unified Presence. Industry-focused EIM platforms such as Reuters Messaging and Bloomberg Messaging also provide IM abilities to financial services companies.
The adoption of IM across corporate networks outside of the control of IT organizations creates risks and liabilities for companies who do not effectively manage and support IM use. Companies implement specialized IM archiving and security products and services to mitigate these risks and provide safe, secure, productive instant messaging abilities to their employees. IM is increasingly becoming a feature of enterprise software rather than a stand-alone application.
IM products can usually be categorised into two types: Enterprise Instant Messaging (EIM) and Consumer Instant Messaging (CIM). Enterprise solutions use an internal IM server, however this isn't always feasible, particularly for smaller businesses with limited budgets. The second option, using a CIM provides the advantage of being inexpensive to implement and has little need for investing in new hardware or server software.
For corporate use, encryption and conversation archiving are usually regarded as important features due to security concerns. There are also a bunch of open source encrypting messengers. Sometimes the use of different operating systems in organizations requires use of software that supports more than one platform. For example, many software companies use Windows in administration departments but have software developers who use Linux.
An Instant Message Service Center (IMSC) is a network element in the mobile telephone network which delivers instant messages. When a user sends an IM message to another user, the phone sends the message to the IMSC. The IMSC stores the message and delivers it to the destination user when they are available. The IMSC usually has a configurable time limit for how long it will store the message. Few companies who make many of the IMSCs in use in the GSM world are Miyowa, Followap and OZ. Other players include Acision, Colibria, Ericsson, Nokia, Comverse Technology, Now Wireless, Jinny Software, Miyowa, Feelingk and few others.
Major IM services are controlled by their corresponding companies. They usually follow the client-server model when all clients have to first connect to the central server. This requires users to trust this server because messages can generally be accessed by the company. Companies can be compelled to reveal their user's communication. Companies can also suspend user accounts for any reason. There is the class of instant messengers that uses the serverless model, which doesn't require servers, and the IM network consists only of clients. There are several serverless messengers: RetroShare, Tox, Bitmessage, Ricochet, Ring. Serverless messengers are generally more secure because they involve fewer parties.
Conversational commerce is e-commerce via various means of messaging:
Crackers (malicious or black hat hackers) have consistently used IM networks as vectors for delivering phishing attempts, "poison URLs", and virus-laden file attachments from 2004 to the present, with over 1100 discrete attacks listed by the IM Security Center in 2004–2007. Hackers use two methods of delivering malicious code through IM: delivery of viruses, trojan horses, or spyware within an infected file, and the use of "socially engineered" text with a web address that entices the recipient to click on a URL connecting him or her to a website that then downloads malicious code.
Viruses, computer worms, and trojans usually propagate by sending themselves rapidly through the infected user's contact list. An effective attack using a poisoned URL may reach tens of thousands of users in a short period when each user's contact list receives messages appearing to be from a trusted friend. The recipients click on the web address, and the entire cycle starts again. Infections may range from nuisance to criminal, and are becoming more sophisticated each year.
IM connections sometimes occur in plain text, making them vulnerable to eavesdropping. Also, IM client software often requires the user to expose open UDP ports to the world, raising the threat posed by potential security vulnerabilities.
In addition to the malicious code threat, the use of instant messaging at work also creates a risk of non-compliance to laws and regulations governing use of electronic communications in businesses.
In the United States alone there are over 10,000 laws and regulations related to electronic messaging and records retention. The better-known of these include the Sarbanes–Oxley Act, HIPAA, and SEC 17a-3.
Clarification from the Financial Industry Regulatory Authority (FINRA) was issued to member firms in the financial services industry in December, 2007, noting that "electronic communications", "email", and "electronic correspondence" may be used interchangeably and can include such forms of electronic messaging as instant messaging and text messaging. Changes to Federal Rules of Civil Procedure, effective December 1, 2006, created a new category for electronic records which may be requested during discovery in legal proceedings.
Most nations also regulate use of electronic messaging and electronic records retention in similar fashion as the United States. The most common regulations related to IM at work involve the need to produce archived business communications to satisfy government or judicial requests under law. Many instant messaging communications fall into the category of business communications that must be archived and retrievable.
In the early 2000s, a new class of IT security provider emerged to provide remedies for the risks and liabilities faced by corporations who chose to use IM for business communications. The IM security providers created new products to be installed in corporate networks for the purpose of archiving, content-scanning, and security-scanning IM traffic moving in and out of the corporation. Similar to the e-mail filtering vendors, the IM security providers focus on the risks and liabilities described above.
With rapid adoption of IM in the workplace, demand for IM security products began to grow in the mid-2000s. By 2007, the preferred platform for the purchase of security software had become the "computer appliance", according to IDC, who estimate that by 2008, 80% of network security products will be delivered via an appliance.
By 2014 however, the level of safety offered by instant messengers was still extremely poor. According to a scorecard made by the Electronic Frontier Foundation, only 7 out of 39 instant messengers received a perfect score, whereas the most popular instant messengers at the time only attained a score of 2 out of 7. A number of studies have shown that IM services are quite vulnerable for providing user privacy.
|Instant messenger client||Company||Usage|
|Discord||Discord inc.||130 million users (May 2018)|
|eBuddy XMS||eBuddy||250 million users (September 2011)|
|Facebook Messenger||900 million active users (April 2016)|
|iMessage||Apple Inc.||140 million users (June 2012)|
|Kik Messenger||Kik Interactive||300 million users (May 2016) |
|Line||Naver Corporation||217 million monthly active users (2016)|
|Skype||Microsoft Corporation||560 million users (April 2010), 34 million peak online (February 2012)|
|Snapchat||Snap Inc.||301 million monthly active users (2016)|
|Telegram||Telegram Messenger LLP||200 million monthly active users (March 2018)|
|Tencent Holdings Limited||889 million users (2016)|
|1200 million monthly active users (January 2017)|
|Instant messenger client||Company||Usage|
|BlackBerry Messenger||BlackBerry||91 million total users (October 2014)|
|Hike Messenger||Hike Messenger||70 million active users (October 2015)|
|Gadu-Gadu||GG Network S.A.||6.5 million users active daily (majority in Poland) (June 2010)|
|IBM Sametime||IBM Corp.||15 million (enterprise) users (Unknown)|
|ICQ||ICQ LLC.||11 million total users (July 2014)|
|IMVU||IMVU, inc.||1 million users (June 2007)|
|Paltalk||Paltalk.com||5.5 million monthly unique users (August 2013)|
|XMPP (Protocol used by multiple clients)||XMPP Standards Foundation||1200+ million (September 2011)|
|Instant messenger client||Company||Usage|
|AIM||AOL, Inc||Closed in December 2017|
|MXit||MXit Lifestyle (Pty) Ltd.||Closed in September 2016|
|Windows Live Messenger||Microsoft Corporation||Closed in April 2013, China in October 2014|
|Xfire||Xfire, Inc.||Closed in June 2015|
|Yahoo! Messenger||Yahoo!, Inc.||Closed in July 2018|
|RTC||rtcim.com||10 million users|
PalTalk, a profitable group video chat site that’s been around for more than a decade and has about 5.5 million monthly uniques [...]
AIM (AOL Instant Messenger) 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.
AIM was popular from the late 1990s to the late 2000s in North America, and was the leading instant messaging application in that region. AIM's popularity declined steeply in the early 2010s as Internet social networks like Facebook and Twitter gained popularity, and its fall has often been compared with other once-popular Internet services such as Myspace.In June 2015, AOL was acquired by Verizon Communications. In June 2017, Verizon combined AOL and Yahoo into its subsidiary Verizon Media (formally Oath Inc). The company discontinued AIM as a service on December 15, 2017.Adium
Adium is a free and open source instant messaging client for macOS that supports multiple IM networks, including Windows Live Messenger, Yahoo! Messenger, Google Talk, AIM, ICQ and XMPP. It is written using macOS's Cocoa API, and it is released under the GNU General Public License and many other licenses for components that are distributed with Adium.BitlBee
BitlBee is a cross-platform IRC instant messaging gateway, licensed under the terms of the GNU General Public License.
BitlBee communicates with the user via the IRC protocol, providing a gateway to popular chat networks such as AIM and ICQ (via OSCAR), Microsoft Messenger service (via MSNP), Yahoo! (via YMSG) and Google Talk and Facebook Messenger (via MQTT with a plugin) and the microblogging networks Twitter, Identi.ca, and GNU Social. Since version 3.0, BitlBee can be built to use the libpurple library, which supports file transfers on many IM networks, and supports GaduGadu, QQ and other less well-known protocols. Off-the-record messaging is supported by Bitlbee. It supports the display of remote user status using the IRC voice attribute: online users are shown with voice, away users are shown without. Many IRC commands such as /WHO and /QUERY are available, though the capabilities of the remote IM protocols limit which IRC commands will work.It can be installed and operated on a user's personal computer, a local server, or accessed on public gateway servers. A user registers with the BitlBee server for future credentials storage. Service protocols are added along with their credentials; following this, the software will display the user's buddy list as normal IRC users in a channel. Conversations can be public, or use the private message facility of IRC.BitlBee runs on Linux, Unix, BSD, Windows, AmigaOSand Mac OS X.
The software has been reviewed positively. Vladi Belperchinov-Shabanski wrote that the software made his "dream come true", of only needing a single chat client open on his desktop, to access multiple IM protocols.Comparison of instant messaging protocols
The following is a comparison of instant messaging protocols. It contains basic general information about the protocols.Empathy (software)
Empathy is an instant messaging (IM) and voice over IP (VoIP) client which supports text, voice, video, file transfers, and inter-application communication over various IM protocols.
Empathy was created by forking the Gossip project started by Michael Hallendal, Richard Hult and later maintained by Martyn Russell. It was forked because there were disagreements amongst contributors about the backend at the time. It was initially completely XMPP based (similar to Google Talk and Facebook's chat implementations), but others wanted it to use the Telepathy stack. This led to the forking and new name Empathy.
Empathy also provides a collection of reusable graphical user interface widgets for developing instant messaging clients for the GNOME desktop. It is written as extension to the Telepathy framework, for connecting to different instant messaging networks with a unified user interface.
Empathy has been included in the GNOME desktop since its version 2.24, in Ubuntu since version 9.10 (Karmic Koala), and in Fedora since version 12 (Constantine); Empathy has replaced Pidgin as their default messenger application.Fire (instant messaging client)
Fire is an instant messaging client for Mac OS X (previously for OPENSTEP), that can access IRC, XMPP, AIM, ICQ, Microsoft, Yahoo!, and Bonjour. All services are built on GPL’d libraries, including firetalk, libfaim, libicq2000, libmsn, XMPP, and libyahoo2. Fire supports OS X v10.1 and higher.
The latest version of Fire is 1.5.6. The program is released under the GNU General Public License.
On 2007-02-23, it was announced that there would be no future versions of Fire released. The official Fire website stated there were several reasons, the biggest being the loss of developers, followed by the fact that most of the libraries used by Fire are no longer in active development. Two of Fire's developers joined the Adium team and wrote a transition path for users to move from Fire to Adium. The announcement recommended Adium for future IM needs.Gadu-Gadu
Gadu-Gadu (Polish for "chit-chat"; commonly known as GG or gg) is a Polish instant messaging client using a proprietary protocol. Gadu-Gadu was the most popular IM service in Poland, with over 15 million registered accounts and approximately 6.5 million users online daily. Gadu-Gadu’s casual gaming portal had some 500,000 active users at the end of March 2009. Users send up to 300 million messages per day.Gadu-Gadu is financed by the display of advertisements. The developer is based in Warsaw, Poland but the company is wholly owned by the South African media giant Naspers.Instant Messaging and Presence Protocol
Instant Messaging and Presence Protocol (IMPP) was an IETF working group created for the purpose of developing an architecture for simple instant messaging and presence awareness/notification. It was created on 1999-02-25 and concluded on 2004-09-08.Jami (software)
Jami (formerly GNU Ring, SFLphone) is a SIP-compatible softphone and SIP-based instant messenger for Linux, Microsoft Windows, OS X, iOS and Android.
Developed and maintained by the Canadian company Savoir-faire Linux, and with the help of a global community of users and contributors, Jami positions itself as a potential free Skype replacement.Jami is free and open-source software released under the GNU General Public License. In November 2016, it became part of the GNU Project.Two account types are currently available, and many of each type can be configured concurrently. Both types offer similar features including messaging, video and audio. The account types are SIP and Ring. A SIP account enables the Jami softphone to connect to a standard SIP server and a Ring account can register (or use an account set up) on the decentralised Jami network which requires no central server.
By adopting distributed hash table technology (as used, for instance, within the BitTorrent network), Jami creates its own network over which it can distribute directory functions, authentication and encryption across all systems connected to it.Packages are available for all major Linux distributions including Debian, Fedora, and Ubuntu. Separate GNOME and KDE versions are available. Documentation is available on Ring's Tuleap wiki.As of 18 December 2018, Ring was renamed to Jami.Kopete
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.List of defunct instant messaging platforms
Below is a list of defunct instant messaging platforms.
Name, When discontinued - Type of clientPidgin (software)
Pidgin (formerly named Gaim) 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 into various services from one application.
The number of Pidgin users was estimated to be over three million in 2007.Pidgin is widely used for its Off-the-Record Messaging (OTR) plugin, which offers end-to-end encryption. For this reason it is included in the privacy- and anonymity-focused operating system Tails.Psi (instant messaging client)
Psi is a free instant messaging client for the XMPP protocol (including such services as Google Talk) which uses the Qt toolkit. It runs on Linux (and other Unix-like operating systems), Windows, macOS and eComStation (OS/2).Ready-to-install deb and RPM packages are available for many Linux distributions. Successful ports of Psi were reported for Haiku, FreeBSD and Sun Solaris operating systems.
Due to Psi's free/open-source nature, several forks have appeared, which occasionally contain features that may appear in future official Psi versions. These official and unofficial builds are documented on their external wiki page.RetroShare
RetroShare is a free and open-source peer-to-peer communication and file sharing app based on a friend-to-friend network built on GNU Privacy Guard (GPG). Optionally, peers may communicate certificates and IP addresses from and to their friends.SIMPLE (instant messaging protocol)
SIMPLE, the Session Initiation Protocol for Instant Messaging and Presence Leveraging Extensions, is an instant messaging (IM) and presence protocol suite based on Session Initiation Protocol (SIP) managed by the Internet Engineering Task Force. Contrary to the vast majority of IM and presence protocols used by software deployed today, SIMPLE is an open standard like XMPP.Tkabber
Tkabber is a GPL instant messaging client for the XMPP protocol which uses the Tk toolkit for the GUI. It runs on anything to which Tcl/Tk is ported: almost any X-based system (namely, any Linux and *BSD, Solaris, etc.), Microsoft Windows, and Mac OS X.Tox (protocol)
Tox is a peer-to-peer instant-messaging and video-calling protocol that offers end-to-end encryption. The stated goal of the project is to provide secure yet easily accessible communication for everyone. A reference implementation of the protocol is published as free and open-source software under the terms of the GNU General Public License (GPL) version 3 or later.Trillian (software)
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), ICQ, 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.
Trillian no longer supports Windows Live Messenger or Skype as these services have combined and Microsoft chose to discontinue Skypekit. They also no longer support connecting to MySpace, and no longer support a distinct connection for Gmail, Hotmail or Yahoo! Mail although these can still be connected to via POP3 or IMAP.
Initially released July 1, 2000, as a freeware IRC client, the first commercial version (Trillian Pro 1.0) was published on September 10, 2002. The program was named after Trillian, a fictional character in The Hitchhiker's Guide to the Galaxy by Douglas Adams. A previous version of the official web site even had a tribute to Douglas Adams on its front page. On August 14, 2009, Trillian "Astra" (4.0) for Windows was released, along with its own Astra network. Trillian 5 for Windows was released in May 2011, and Trillian 6.0 was initially released in February 2017.Windows Messenger
Windows Messenger is a discontinued instant messaging client included in Windows XP. Designed for use by both corporate and home users, it was originally created, in 2001, as a streamlined and integrated version of MSN Messenger. It was later upgraded in 2004, when it was made available for Windows 2000 and Windows Server 2003. Since then, its development stopped. It was superseded by Windows Live Messenger and Microsoft Lync.