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Gas fee
A fee paid to the network to execute a transaction or contract. It fluctuates with network congestion.
Category: SecurityRelated terms
Blockchain
A public, shared database of transactions that nobody owns. Records are chained and immutable, verified by a network of computers, not one central authority.
L1 / L2
L1 is a base blockchain (Bitcoin, Ethereum). L2 is a layer on top of it that makes transactions faster and cheaper.
DeFi
Decentralized finance: lending, swaps and yield via smart contracts, with no bank in the middle. It all runs on-chain and is publicly verifiable.