Proof of work (PoW) + PoS-based public blockchains in Ethereums upcoming Casper implementation. Opposed to the PoW consensus protocol, the PoS protocol achieves consensus through stakers, sometimes referred to as minters who “stake” their coins by locking them down in specialized wallets. With stakers at work, mining will become redundant, meaning the Ethereum network post-Casper will rely on stakers and staking pools instead of miners for its operability.