Hello and welcome to the programme. Now, five years ago, we devoted a bottom line to

Bitcoin with a bit of added blockchain. It was a very trendy topic at the time. A Bitcoin was then

worth £400 or so and we did a bit of successful demystification on that topic.

But since then, a lot has happened. For one thing, there was a surge in the value of Bitcoin,

up to a peak of 15,000 pounds. There was a huge flurry of new cryptocurrencies launched to the market.

These were these were called

ICOs initial coin offerings and they hit a peak, probably more accurately, a bubble in 2017.

The concept of the blockchain was suddenly ridiculously trendy and was proclaimed to be a potential

solution to almost every problem under the sun,

even including the Irish border after Brexit.

Well, the dust has now settled, the bubble burst,

but a Bitcoin is still worth £8,000.

And at this point, we thought we should revisit and update the topic of cryptocurrencies and blockchain technology.

What works, what's left? And one very important reason for doing this now is the announcement by Facebook

that it is to launch its own currency next year, Libra, which threatens to become huge.

Now I appreciate we will need to refresh all our memories of what a cryptocurrency is.

Some of the conversation may become perhaps a little bit technical, but we're not going to leave anyone behind as we go through.

But I also want us to think about future applications of blockchain.

And I'm happily joined by three guests who can help us through all of this.

First up, we have an academic, Catherine Mulligan, Chief Technology Officer of Gov Tech Labs and Datanet at UCL in London, and formerly

Associate Director at Imperial College there, the Centre for Cryptocurrency Research and Engineering.

And Catherine, just tell us what your kind of area of research is. Yeah, so my overall

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