Staking is common in networks that use the Proof of Stake (PoS) algorithm. PoS is an alternative to Proof of Work (PoW). PoW blockchains use mining to validate and validate new blocks. This is a time consuming and costly process.
PoS chains do this by staking cryptocurrencies. The very process of mining new blocks in such networks is called forging. Anyone can become a validator. To do this, the user only needs to buy cryptocurrency and hold it. PoS validators are selected based on the number of coins in the system - in the stake. The more tokens a user invests in a stake, the higher probability that he will become a validator.
Formation of blocks using the PoS algorithm allows to increase the scalability of the blockchain network. Related to this is the transition of the Ethereum network from PoW to PoS.