Casper
Web3 / crypto history
Casper is a research project that developed the Proof of Stake consensus mechanism adopted by Ethereum. It represents a fundamental shift from energy-intensive Proof of Work to a more efficient validation model where validators are chosen based on their stake in the network rather than computational power. Casper introduced the concept of "finality" in blockchain consensus, meaning that once a block is confirmed by validators and they put up collateral, that block cannot be reversed without significant economic loss. This breakthrough made Ethereum's transition to Proof of Stake technically feasible and economically sound. Example: Ethereum's transition to the Beacon Chain in December 2020 implemented Casper FFG (Friendly Finality Gadget), which served as the consensus layer for the network's eventual complete shift away from mining in September 2022 during the Merge event. Why it matters for crypto history: Casper represents a pivotal moment in blockchain evolution, demonstrating that decentralized networks could operate securely without wasteful mining, influencing countless other projects to explore Proof of Stake alternatives.
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