Tech and AI: 4. Cryptocurrency, Blockchain and the Web version 3.0

You might be wary of using digital currencies, but you probably already do.

Salaries, benefits and pensions are now paid direct to banks, and when you buy a coffee, you may well use a contactless card to pay, without a flutter of a 5 pound note in sight.

So what are online cryptocurrencies like Bitcoin, and why won't some people touch those with a barge pole? And when you hear about them, another word always pops up - Blockchain. What does it do? And how could both become important when we start to use the next version of the Internet, called web 3.0?

Technology has already completely altered our lives, and Artificial Intelligence may transform our world to an even greater degree. This series is your chance to get back to basics and really understand key technology terms. What's an algorithm? where is "the Cloud" and what are VR and AR? What's the difference between machine and deep learning in artificial intelligence, and is it just our jobs under threat, or is it much worse than that? And before we get to the destruction of humanity, should we all be using Bitcoin? Our experts will explain in the very simplest terms everything you need to know about the tech that underpins your day. We'll explore the rich history of how all these systems developed, and where they may be going next.

Presenter: Spencer Kelly Producers: Ravi Naik and Nick Holland Editor: Clare Fordham Production Coordinator: Janet Staples