Mastering Blockchain - Second Edition

Transaction receipts

Transaction receipts are used as a mechanism to store the state after a transaction has been executed. In other words, these structures are used to record the outcome of the transaction execution. It is produced after the execution of each transaction. All receipts are stored in an index-keyed trie. The hash (Keccak 256-bit) of the root of this trie is placed in the block header as the receipts root. It is composed of four elements that are described here:

• The post-transaction state: This item is a trie structure that holds the state after the transaction has been executed. It is encoded as a byte array.
• Gas used: This item represents the total amount of gas used in the block that contains the transaction receipt. The ...