A method represents the function executed in the transaction, also known as a function call. On the explorer, this method can be displayed as either a text signature(human readable form), or bytes signature(hexadecimal form). Basically, the method defines the transaction type.
For developers who want to display a certain method as human readable on the explorer, please check out this article.
The explorer uses the 4byte signature database to decode the bytes signature and display it in a human readable form.
Let's take this transaction as an example. On the explorer, it can be seen that the method used was Add Limit Order list, which is its text signature. It has the bytes signature 0x2dbc695e on the 4byte database.
Function calls are specified by the first four bytes of data sent with a transaction
(transaction input data). These 4-byte signatures are defined as the first four bytes of the Keccak hash (SHA3) of the canonical representation of the function signature. The database also contains mappings for event signatures. Unlike function signatures, they are defined as 32-bytes of the Keccak hash (SHA3) of the canonical form of the event signature. Since this is a one-way operation, it is not possible to derive the human readable representation of the function or event from the bytes signature. The 4byte database allows mapping those bytes signatures back to their human-readable versions.
Our explorer displays the text signature by default when the method is registered on the 4byte database. If a user wants to find the bytes signature for, let's say, this transaction, it can be done using Transaction Input Data. As mentioned above, the first four bytes of transaction data represent the bytes signature. They can be extracted from Input Data, and then looked up on 4byte.
For any additional questions, please view our other knowledge base articles or contact a support team member via the chat button. Examples are for illustrative purposes only.