A hash is a 256 bit representation of what the input data was. It's like an index card that can be easily, you know, you can look through them really quickly and not have to dig into each book or block. So I think it's worth it today to kind of redefine what a hash is because we are going to be talking about them a lot.
In this introductory episode, we discuss what makes up blocks and block headers. We also cover a bit about state vs history, what exactly makes up a transaction and do a quick intro to a Merkle Tree.
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