Okay, so what’s the blockchain? It’s a database. Unlike most databases, it’s not controlled by one entity and it’s not easily rewritten. Instead, it’s a ledger, a permanent, examinable, public database. One can use it to record transactions of various sorts. It would be a really good way to keep track of property records, for example. Instead, we have title insurance, unsearchable folders of deeds in City Hall and often dusty tax records.