A <a href="/en/glossary/network-economics/gas-fee/">Gas Fee</a> is what a user pays for a transaction to be processed and included by a blockchain network — in most modern designs, part gets burned and part goes to validators — fundamentally the price paid for occupying limited <a href="https://crypto-bible.com/en/glossary/blockchain-fundamentals/block/" target="_blank" rel="noopener">Block</a> space and computational resources. It isn't a fixed amount, but a market price that floats with network congestion.