Parameter for [eth_newFilter](JSON-RPC-API-Methods.md#eth_newfilter) and [eth_getLogs](JSON-RPC-API-Methods.md#eth_getlogs). Used to [filter logs](../Using-Pantheon/Accessing-Logs-Using-JSON-RPC.md).
| **fromBlock** | Quantity | Tag | Optional | Integer block number or `latest`, `pending`, `earliest`. See [Block Parameter](Using-JSON-RPC-API.md#block-parameter). Default is `latest`. |
| **toBlock** | Quantity | Tag | Optional | Integer block number or `latest`, `pending`, `earliest`. See [Block Parameter](Using-JSON-RPC-API.md#block-parameter). Default is `latest`. |
| **address** | Data | Array | Optional | Contract address or array of addresses from which [logs](../Using-Pantheon/Events-and-Logs.md) originate. |
| **topics** | Array of Data, 32 bytes each | Optional | Array of topics by which to [filter logs](../Using-Pantheon/Events-and-Logs.md#topic-filters). |
| **blockhash** |Data, 32 bytes | Optional | Hash of block for which to return logs. If `blockhash` is specified, `fromBlock` and `toBlock` cannot be specified. |
## Log Object
Returned by [eth_getFilterChanges](JSON-RPC-API-Methods.md#eth_getfilterchanges) and [transaction receipt objects](#transaction-receipt-object) can contain an array of log objects.
| **topics** | Array of Data, 32 bytes each | [Event signature hash](../Using-Pantheon/Events-and-Logs.md#event-signature-hash) and 0 to 3 [indexed log arguments](../Using-Pantheon/Events-and-Logs.md#event-parameters). |
| **gasCost** | Integer | Cost in wei of each gas unit |
| **depth** | Integer | Execution depth |
| **exceptionalHaltReasons** | Array | One or more strings representing an error condition that caused the EVM execution to terminate. These indicate that EVM execution terminated for reasons such as running out of gas or attempting to execute an unknown instruction. Generally a single exceptional halt reason is returned but it is possible for more than one to occur at once. |
| **stack** | Array of 32 byte arrays | EVM execution stack before executing current operation |
| **memory** | Array of 32 byte arrays | Memory space of the contract before executing current operation |
| **storage** | Object | Storage entries changed by the current transaction |
## Transaction Object
Returned by [eth_getTransactionByHash](JSON-RPC-API-Methods.md#eth_gettransactionbyhash), [eth_getTransactionByBlockHashAndIndex](JSON-RPC-API-Methods.md#eth_gettransactionbyblockhashandindex), and [eth_getTransactionsByBlockNumberAndIndex](JSON-RPC-API-Methods.md#eth_gettransactionbyblocknumberandindex).
| **from** | Data, 20 bytes | Optional | Address from which transaction is sent. |
| **to** | Data, 20 bytes | Required | Address to which transaction is directed. |
| **gas** | Quantity, Integer | Optional | Gas provided for the transaction execution. `eth_call` consumes zero gas, but this parameter might be needed by some executions. `eth_estimateGas` ignores this value. |
| **gasPrice** | Quantity, Integer | Optional | Price used for each paid gas. |
| **value** | Quantity, Integer | Optional | Value sent with this transaction. |
| **data** | Data | Optional | Hash of the method signature and encoded parameters. For details, see [Ethereum Contract ABI](https://github.com/ethereum/wiki/wiki/Ethereum-Contract-ABI). |