Lemmy is an open-source, federated link aggregator and discussion platform designed as a decentralized alternative to platforms like Reddit. It aims to provide a customizable, privacy-focused, and community-driven space for sharing links, engaging in discussions, and forming online communities.

At its core, Lemmy allows users to create communities or join existing ones. These communities can focus on specific topics, interests, or themes, fostering engagement among like-minded individuals. Users can submit links to content, such as articles, videos, or images, and the community can vote on and discuss these submissions.

One of Lemmy’s defining features is its federated architecture. Rather than relying on a single centralized server, Lemmy instances can be created and interconnected, forming a network of independent communities. Each instance can have its own moderation policies, community guidelines, and design while remaining part of the larger Lemmy federation. This federated model enables decentralization and community autonomy, allowing instances to operate independently and moderate content according to their own standards.

Lemmy embraces the ActivityPub protocol, a widely adopted standard for federated social networking. This protocol enables interoperability between different platforms that support it, allowing users on Lemmy instances to interact with users on other federated platforms. It encourages collaboration, discovery, and cross-community engagement.

Privacy and user control are fundamental principles of Lemmy. It emphasizes user anonymity and allows users to control their data and privacy settings. With Lemmy, users can choose pseudonyms and decide what personal information, if any, they want to share. This focus on privacy helps create a safe and secure environment for open discussions.

https://join-lemmy.org/docs/en/introduction.html