Definition
What is Function selector?
A function selector is the first four bytes of the keccak-256 hash of a function's signature, used at the start of calldata to tell the contract which function to run.
For example transfer(address,uint256) hashes to 0xa9059cbb. Explorers and debuggers decode selectors using the ABI.
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Definition by Adwait Keshari, founder of Monsmith.
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