Each of the parachains specializes in one type of application. Validators verify the transactions emanating from the Parachains before storing them on the relay chain. You can check this link applicature.com/ to get more information on para chain developers.
Nominated proof of stake is a distinctive aspect of their safety but not the only means. Validators on the relay chain have a vested interest with their stake deposits, with additional contributions from those who nominate them. Both incur penalties for malicious, dishonest, or incompetent behavior.
Additionally, the security of blocks, each containing the encrypted data of individual parachains, verified by collators, is confirmed by a super-majority vote of validators, at a minimum of fourteen, representing the blocks.
Parachains retrieve the mathematical truth from the Polkadot Relay Chain. This means they can operate cheaply and with predictable transaction costs while still having the advantages of a permissionless blockchain like Bitcoin orEthereum. On the upside, Polkadot will have several Parachains which might want to use our digital identity solutions.
Proof-of-stake works in combination with economic incentives to discourage cheating. The participants are typically called validators who have skin the game with their token deposits.
Their job is to verify transactions on the core network. Should a transaction turn out to be fraudulent or deceitful, they incur financial penalties (slashing). Conversely, the validators benefit from the network’s overall growth and the fees they earn from verifying transactions.