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 in to various services from a single application, with a single interface for both popular and obsolete protocols (from AIM to Discord), thus avoiding the hassle of having to deal with new software for each device and protocol.

The emulation was not based on reverse engineering, but instead relied on information about the protocol that AOL had published on the web.

[6] On 6 July 2015, Pidgin scored seven out of seven points on the Electronic Frontier Foundation's secure messaging scorecard.

[9] They have received points for having communications encrypted in transit, having communications encrypted with keys the providers don't have access to (end-to-end encryption), making it possible for users to independently verify their correspondent's identities, having past communications secure if the keys are stolen (forward secrecy), having their code open to independent review (open source), having their security designs well-documented, and having recent independent security audits.

The development team has stated that other protocols plugins will be available later pending their re-implementation, and that future experimental releases will follow a three-month cadence.

[13] On April 6, 2007, the project development team announced the results of their settlement with AOL, which included a series of name changes: Gaim became Pidgin, libgaim became libpurple, and gaim-text (the command-line interface version) became Finch.

Following the settlement, it was announced that the first official release of Pidgin 2.0.0 was hoped to occur during the two weeks from April 8, 2007.

They can be used to add support for protocols, which is useful for those such as Skype or Discord which have licensing issues (however, the users' data and interactions are still subject to their policies and eavesdropping).

[21] Further features include support for themes, emoticons, spell checking, and notification area integration.

[33] Such features include: BitlBee and Minbif are IRCd-like gateways to multiple IM networks, and can be compiled with libpurple to increase functionality.