0x0are legacy transactions that use the transaction format existing before typed transactions were introduced in EIP-2718. They contain the parameters
s. Legacy transactions don’t use access lists or incorporate EIP-1559 fee market changes.
0x1are transactions introduced in EIP-2930. They contain, along with the legacy parameters, an
accessListparameter, which specifies an array of addresses and storage keys that the transaction plans to access (an access list). Access list transactions must specify an access list, and they don’t incorporate EIP-1559 fee market changes.
0x2are transactions introduced in EIP-1559, included in Ethereum's London fork. EIP-1559 addresses the network congestion and overpricing of transaction fees caused by the historical fee market, in which users send transactions specifying a gas price bid using the
gasPriceparameter, and miners choose transactions with the highest bids.
gasPrice, and instead use an in-protocol, dynamically changing base fee per gas. At each block, the base fee per gas is adjusted to address network congestion as measured by a gas target.
accessListparameter and legacy parameters except for
maxPriorityFeePerGasparameter, which specifies the maximum fee the sender is willing to pay per gas above the base fee (the maximum priority fee per gas), and a
maxFeePerGasparameter, which specifies the maximum total fee (base fee + priority fee) the sender is willing to pay per gas.
maxPriorityFeePerGasor, if the base fee per gas +
maxFeePerGas, it pays a priority fee as priced by
maxFeePerGasminus the base fee per gas. The base fee is burned, and the priority fee is paid to the miner that included the transaction. A transaction’s priority fee per gas incentivizes miners to include the transaction over other transactions with lower priority fees per gas.