The Proof of Stake (PoS), or proof of stake in French, is a consensus mechanism used by certain blockchains to validate transactions and secure the network in a more energy-efficient manner than the Proof of Work (PoW) used by Bitcoin.

In a PoS system, participants called validators must lock up an amount of cryptocurrency (their "stake") in order to have the right to validate blocks. The more tokens a validator puts at stake, the more likely they are to be selected to produce a block and receive a reward.

Advantages of Proof of Stake:

• Very low energy consumption compared to traditional mining,

• More accessible, as it does not require specialized hardware (like ASICs),

• Encourages holding tokens (staking), which supports the network.

Blockchains using PoS:

• Ethereum (since The Merge in 2022),

• Cardano, Solana, Polkadot, Tezos, etc.