I'm trying to understand how Ethereum stores data that I send, if I have a transaction that sends 20 bytes of data to a contract then before the contract has even been executed the blockchain has access to my sender account, the 20 bytes of data and my tx signature.
Does this get stored in the blockchain? Can I access it via an API?
Or do I need to make sure my contract uses storage to save the 20 bytes because its not saved in the blockchain?
I would have thought the blockchain needs to store the full tx including 20 bytes so that other nodes can replicate it.