Gas fee

Fee paid to validators for processing a transaction on a blockchain. Priced in the network's native token (ETH on Ethereum, SOL on Solana). Varies with network congestion — Ethereum fees can spike from $1 to $100+ during NFT mints or memecoin manias.

L2s (Arbitrum, Optimism, Base) batch transactions to compress L1 gas costs. Solana keeps fees consistently low through high throughput.