 Whatapha asks, is lightning the same as in a UTXO model, or is only the invoice amount sent? Is lightning a blockchain? No. Lightning is not a blockchain. Lightning is a routable network of smart contracts that are exchanged between parties. In the case of the Lightning network, those smart contracts are usually signed Bitcoin transactions. But they can also be signed Litecoin transactions, because it's a multi-currency network. Participants in the network exchange signed Bitcoin transactions that they don't send on the public Bitcoin blockchain, but which the public Bitcoin blockchain provides security for. Lightning is different than Bitcoin. It runs on top of Bitcoin and other blockchains. It provides a way to very quickly exchange value that is confirmed instantly and can be for very small amounts, and scales to a much larger degree than a blockchain does. But it uses all of the security of the underlying blockchain, so it has the same security model as the underlying blockchain. No, lightning isn't a blockchain. Marius asks, how can I practically participate in the Lightning network? Do all it support this? Should I download and run a node? Actually, there are a number of ways you can participate in the Lightning network that do not involve downloading and running a node. The best way, of course, is to download them on a node, but you may find that a bit difficult to configure. You have to run a full Bitcoin node, at least at the moment. In the future, we may see that work with a lightweight client called Neutrino. For the moment, you have to run a full Bitcoin node and a Lightning node on top of it. That is fairly technical, so you might find that difficult to do. There is another way that allows you to run a full node that is easier, and that is a desktop wallet called ZAP. The ZAP wallet includes the functionality of a full node with a nice user interface, so you can try that. It will take up quite a few gigabytes on your hard drive, I think, at last count, almost 200 plus gigabytes. That is a single full node, if you don't have one already. But an easier way is to use a number of mobile wallets that already exist for Lightning. For example, I have some running on my mobile at the moment, both on Android and iOS, although you will find more on Android. Blue wallets and the Bitcoin Lightning wallets are two wallets that currently support Lightning transactions. You can try those as well as Eclare, E-C-L-A-I-R, which means Lightning in French. Those three wallets work pretty well, and they can introduce you to the world of Lightning without having to run a full node per name. Marius asks again, was the recent testing of Lightning payments successful in terms of satisfying what Lightning was designed to serve? It's not really like there's specific testing. Since January of 2018, people have been running on a production network, a production network that has more than 6,000 nodes and almost $4 million in capacity on it, and are making thousands of payments every single day using Lightning. It's not like there's a one-off test. This is now a production running network, and it is working spectacularly well. Payments are near instantaneous. That's one of the things that surprises people when they first try Lightning, is the fact that they press the button on their mobile wallet to send a payment. In the time it takes to look away from the mobile and look at the screen of a vendor's point of sale system, or the website where they were making the payment, it's already gone through. It literally takes less than a second in many cases. So when it works, it works spectacularly well. Sometimes payments fail because your node is not well connected enough, or your wallet doesn't set up properly, and these are learning steps. But for the most part, once you have it set up properly, it works very, very well. Marius asks, what is the Lightning torch, and how do people pass it to each other? The Lightning torch is just a game, and it's a game that's intended to test your nodes and wallets set up. You can find out if your nodes and wallets are well set up, and also participate in this business. It's really a simple idea. I send you some money over the Lightning network, and instead of keeping it, what you do is add a small amount, and I believe the last time it was 100,000 Sochi's. So you add a small amount to that payment, and then you find someone else to send it. You send it to them, and they add a small amount, and then they send it forward, so it keeps getting bigger and bigger. Everybody adds just a tiny amount, a dollar or two. And you have to trust who you send it to, because they can keep it. But if you play this game honorably, you send it to the next person with a bit more money, and as it gradually grows, it gets a bit more difficult. And the reason it gets more difficult is because the bigger the payment, the more capacity you need in your nodes, the more capacity you need in the other nodes, the more channels need to be available for you to route, and the fewer routes are available for that kind of capacity. So it gets a bit more challenging. When it gets close to the payment limit, which is 4 million Sochi's, it gets very difficult to forward, but at that point just a few nodes are capable of doing that in their current configuration. So your node has to be very well configured. I participated in this game. My node is very well connected, has plenty of capacity, well-balanced channels. I've been working on it for nine months now, so certainly that one works very well. I had no problem passing the torch. You can try it as a game. If you give someone an invoice in order to receive the torch with the latest amount, and if they can send it to you, and they do, you then have to send it out. There's a chance that they can't send it to you because you don't have enough incoming capacity on your channel. So you'll learn something for sure about participating in this game. In fact, I think at the moment there are a couple of lightning torches going around at different values, so you can try it with a smaller event. David asks, is there a limit from which, if you own below a certain amount of Bitcoin, you cannot transact as it would not be economical for a miner to include these in a block? David, yes, this is called the dust limit. There is a mandatory dust limit of 546 satoshis, that below which your transaction will not be accepted on the network, so you can't make a payment less than 546 satoshis, separately to that. There is a practical limit whereby, if you try to make a payment, the minimum fee that's required by all of the nodes on the network, which is 0.01 millibit, I believe, would be more than the amount you're trying to spend, so it would all get spent on fees before your transaction would really make much sense. The second follow-up question. In the lightning network, is there such a limit, or is it possible to transact as low as one satoshi? This is the exact point. It is possible to transact as low as one satoshi, better yet. On the lightning network, you can actually transact in millisatoshis, which are thousands of a satoshi, and you can transact down to as low as one millisatoshi, one thousandth of a satoshi. Now, you cannot settle millisatoshis on the main blockchain as a clear transaction, so you can't close that channel down to a balance of millisatoshis. What the network does is it rounds up those amounts if you decide to close the channel, but in terms of lightning payments, you can go all the way down to millisatoshis. This is exactly one of the advantages of the lightning network. It breaks the barrier of microtransactions and allows you to push below the dust limit and make transactions that would otherwise be either economically unviable, unminable, or unpropagatable by the network because of other limitations. In lightning, none of those limitations exist. You can go as low as a millisatoshi and do payments that are unimaginably useful without any problems.