In a proof-of-Stake (PoS) system, which came two years after proof-of-work, the validation and mining process is different from PoW in that miners do not have a complex equation to solve, however, it depends on how many coins he/she owns.

This way, the proof-of-stake randomly chooses the miner and he/she receive a transaction fee rather than a reward. This way, the system ensures to remain decentralized since every action is randomized.

A special merit of the proof-of-stake is that it consumes less energy and electricity, thus, it is cost effective, thus, more sustainable than the latter.

However, this system is not free of flaws. In a PoS, there is a potential problem that someone could acquire a very large amount of tokens that he can dominate and take over other validators and become in control of the network.

On the other hand, there is prevention action in place where any sudden rise in the rate of buying the tokens will trigger a sharp rise in the price of token that it becomes impossible for the attacker.