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The Economist.

From The Economist in London, this is Money Talks, a weekly programme about news in the worlds of

business, finance and economics. I'm Philip Coggin, the Buttonwood columnist.

On today's show we'll discuss how bankers can use the technology behind Bitcoin, so-called blockchain.

With me to discuss this is Ludwig Seagler, our technology editor, and Ben Louie, who writes

for us about financial infrastructure.

So Ludwig, let's start with you. who writes for us about financial infrastructure.

So Ludwig, let's start with you.

What is blockchain?

That is a very difficult question and I'm afraid I'm not going to be able to answer that

in two sentences, but what you have to think about is kind of, the blockchain is a type of database.

Usually those databases are controlled by one person, a company, or you can have your

spreadsheet on your computer and you control what's in there. And the blockchain is basically a database that is maintained and updated by all its users collectively.

So they have a mechanism to agree how to update the blockchain and then they kind of bake it into this database and

...