Ouroboros is the consensus protocol of Cardano. Here, we explain what it does and how it's evolving.

With the recent BFT update to the Byron mainnet, and the freshly-published Hydra paper, you'll probably have heard a lot about Ouroboros: the ground-breaking proof-of-stake consensus protocol used by Cardano. Developed as a more energy efficient and sustainable alternative to proof of work, upon which earlier cryptocurrencies – Bitcoin and, currently, Ethereum – are built, Ouroboros was the first blockchain consensus protocol to be developed through peer-reviewed research.

Led by Aggelos Kiayias at the University of Edinburgh, Ouroboros and its subsequent implementations – BFT, Praos, Genesis, Hydra – provide a new baseline to solve some of the world’s greatest challenges, securely and at scale.

Yet recognition begins with education, and we cannot rely on what a technology achieves to convey the how. In this article, we present an overview of the how of Ouroboros. We'll examine the tangibles and cover what each implementation introduces, to further the community's understanding of the protocol, and illustrate why it's such a game changer. A detailed analysis of each implementation can be found in the corresponding whitepapers below. For a broad-stroke explanation of Ouroboros and its implementations, however, read on.

https://iohk.io/en/blog/posts/2020/03/23/from-classic-to-hydra-the-implementations-of-ouroboros-explained/