Due to a lot of advantages compared to more classic methods, for example, Proof of Work, Proof of Stake is much more viable as a consensus system for most of the modern blockchain networks. Probably the biggest advantage that PoS has over others is its energy efficiency: unlike in PoW, complex cryptographic puzzles have to be solved using vast amounts of computational power by miners. Hence, in PoS, the selection of validators is based on how many tokens they own. This reduces the energy consumption by the network drastically and hence, PoS is eco-friendly.
Another important benefit of PoS is scalability: because of a lack of energy-intensive mining, the PoS networks can support higher throughput of transactions. Some features that further increase scalability are often combined with PoS, where blockchains can manage multiple transactions in parallel.
PoS also allows for higher levels of decentralization in that the barriers to entry-thin for validators-go down: instead of costly mining hardware, the participants need to hold a certain amount of cryptocurrency to participate in block validation. This allows participation to be more inclusive, thus widening the circle.
Lastly, PoS systems are normally more secure with accompanying economic incentives. Incentivization of Validators: Further, the validators are incentivized to behave honestly in that misbehavior leads to the loss of some or all staked tokens.
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~ Nesaty