Lemmy (social network)
Lemmy is free and open-source software for running self-hosted social news aggregation and discussion forums. These hosts, known as "instances", communicate with each other using the ActivityPub protocol. History
Lemmy software was created by the user Dessalines on GitHub in February 2019 and licensed under the Affero General Public License. In a 2020 post, Lemmy's co-creator Dessalines wrote about the origin of the name Lemmy. "It was nameless for a long time, but I wanted to keep with the fediverse tradition of naming projects after animals. I was playing that old-school game Lemmings, and Lemmy (from Motorhead) had passed away that week, and we held a few polls for names, and I went with that." According to the Fediverse statistics website the-federation.info, there were less than 100 instances of Lemmy prior to June 2023, increasing to 1521 instances of Lemmy with a total of 66,000 monthly active users . The most popular instances were lemmy.world and lemmy.ml, each with 27,000 and 4,000 monthly active users respectively, . Description
Lemmy is made up of a network of individual installations of the Lemmy software known as "instances" that can intercommunicate. This departs from the centralized, monolithic structure of other social media platforms. It has been described as a federated alternative to Reddit. Users on individual instances submit posts with links, text, or pictures to user-created forums for discussion called "communities". Discussion is in the form of threaded comments. Posts and comments can be upvoted or downvoted. Communities are local to each instance, however users may subscribe to communities, create posts and leave comments across instances. Moderation is conducted by the administrators of each instance and moderators of specific communities. Community names begin with c/ in the URL (e.g lemmy.ml/c/simpleliving) and are uniquely mentionable using the !community@instance format. On each instance, a front page presents the user with popular posts from several communities. These posts can then be filtered according to origin: posts from the instance the user is on, or from all federated instances. It can also be made to only show posts from communities the user has subscribed to. Lemmy instances are generally supported by donations. Relations with other social networks
ActivityPub is the protocol used to allow Lemmy instances to operate as a federated social network. It allows users to interact with compatible platforms such as Kbin. In June 2023, following the announcement of Reddit API service changes that would make the continued use of most third-party Reddit clients unfeasible, community members discussed relocating to Lemmy and other Reddit competitors. In an effort to stop the discussion of such migrations, Reddit banned a user for promoting switching to Lemmy along with theplatform migration on a user and '/r/LemmyMigration' community as a whole. Reporting on sites such as Hacker News about the bans promoted the use of Lemmy only further via the Streisand effect, leading to the reversal of the bans a day later. Third-party software 
Prominent third-party Reddit clients Sync and Boost which had shut down due to changes to the pricing of Reddit's API began working on Lemmy clients, with Sync later relaunching as Sync for Lemmy. External Links 
 A comprehensive list of Lemmy apps
 Third-party services such as Lemmy Community-Browser and Lemmy Explorer provide friendly interfaces for finding interesting communities. References 

2019 software
Fediverse
Free and open-source software
Free software
Free software programmed in Rust
Software using the GNU AGPL license
Web applications