What is Ouroboros, the Cardano Consensus Protocol

Ouroboros is Cardano's consensus protocol, which they consider the first secure Proof of Stake mechanism. Ouroboros processes transaction blocks by dividing the chains into epochs subdivided into time slots, short periods where the network adds new blocks. For each of these slots, the network selects a node as a leader. The selected node is in charge of adding a block to the chain and sending the block to the next leader. The nodes get chosen proportionally based on the number of contributed tokens (Stake Delegation).
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