Gas fees are primarily the transaction costs required to execute transactions and other operations on blockchains like Ethereum.
Gas fees vary depending on network processing capacity and the supply and demand on the blockchains.
The gas fee shown on the transaction confirmation screen is just an estimate, and the actual gas fee may fluctuate depending on network congestion. Please keep this in mind.
The reason for gas fees in NFT transactions
When an NFT is bought or sold on the blockchain, network participants validate the transaction.
As a reward for this validation work, gas fees are distributed to them.
This mechanism imposes a high cost on attempts at fraudulent activity, thus enhancing security.