Ethereum Introduces Blob Data to Support Layer 2 Rollups
Ethereum's calldata and blob data are two distinct ways to make data available on the network. Calldata is part of an Ethereum transaction and becomes part of the blockchain's historical record, while blob data was introduced by EIP-4844 as a temporary, cheaper option for Layer 2 rollups.
Calldata is used for smart contract inputs and transaction data, whereas blob data provides temporary data availability. Blob transactions are a separate mechanism that allows for more efficient publication of large amounts of data to Ethereum.
The key difference between the two lies in their storage and pricing models. Calldata is persistent and consumes regular gas, while blob data is temporary and uses a separate blob gas market. This distinction makes blobs cheaper for rollups but not directly readable by smart contracts.