Lemmy is a self-hosted social link aggregation and discussion platform that operates in the Fediverse, which is made up of independent, loosely interconnected servers used to share files and publish content on the internet. It differs from other social media platforms as it has no centralized or monolithic structure, and instead consists of a network of individual installations called “instances” that can communicate with each other. Lemmy is completely free and open-source, which means there is no advertising, tracking, or secret algorithms. Content is organized into communities so that users can subscribe to topics that interest them and ignore others. Overall, Lemmy is a decentralized alternative to Reddit that offers the same features of sharing links and discussing them in different topic-based communities.