 Hi, Andreas. I'm worried about derivation paths. What it is and what I should know in case I have to use it, could you give us a brief example please? Thanks. This is something that we run into all the time, Simon. And it causes a lot of problems and confusion, especially for new users. If you just write down your mnemonic phrase, you may run into difficulty. And the reason you may run into difficulty is because different wallets implement their derivation, their key derivation in different ways. Let me explain what it is. Let me explain how it works. And then we'll talk about some strategies to protect yourself against any problems with regards to derivation paths. So your mnemonic phrase is 12 to 24 words. It includes a checksum, so you can't get it wrong. And it is mixed with an optional passphrase. If you have no passphrase, it's mixed with the word mnemonic. But if you do have a passphrase, it's mixed with a passphrase instead. Those 12 to 24 words plus the passphrase mix together through a key derivation function that mixes them a few thousand times and then produces a 512-bit master key and chain code, which you never see. But if you did see it, it would be encoded as a base 58 encoding called xpriv. It starts with xpriv, x-p-r-i-v. That is your master private key. And the corresponding master public key would start with xpub. And those are long. They're 512 bits and they contain both a key and a chain code. Now think of this as the root of a tree. And this tree is the so-called hierarchical deterministic wallet, which simply means a wallet where keys can be derived in a sequence in a predictable manner, deterministic, and they're all derived from the same master. So the mnemonic phrase is the ingredient that goes into the cauldron and gets mixed together with the passphrase, and then it produces a root key. And that root key is the root key from which the tree grows. Now this is a weird tree. And the reason it's a weird tree is because at every level of the tree, it branches off into four billion branches. That means that under the root, or above the root, you have four billion possible branches. And then those branches each break into four billion possible branches. And then those branches each break into four billion possible branches. And then those branches break into four billion possible branches, which means that you can't really just shake the tree and see if some keys fall out. Searching that tree is not really possible. So if your wallet just randomly picks a branch and throws your keys on that branch, even if you have the seed necessary to plant the tree and create the root, etc., you don't know where on the tree to look for the keys that produce the addresses that you can find your money on. So that's really the derivation path. And the derivation path is a map for the tree. It usually is represented by a string that starts with the letter M. And M simply means master. So it tells you that starts from the master key. So you will have seen this perhaps written down as something like see that as the path of your first address. That would be in a wallet that's behaving well and is followed what's known as the bit 43 bit 44 standard, which the bit 43 44 standard is a basically a standardized map of where you should hang tree keys on this tree, which branches specifically you should use. And the 44th branch is a particular standard. It means that wallets that follow this standard bit 44 hang all of their keys on the 44th branch. And that's how you identify that they're following this standard. And below that, they create one branch for each of your sub accounts, because with a hierarchical deterministic wallet, you can have account zero, account one, account two to separate your affairs. And then below that, they have one branch for all of the receive addresses and one branch for all of the change addresses. And then below that are the actual keys for the receive and change addresses. So a wallet that follows the bit 44 standard will put those keys in that particular location, which means that if you then import that seed in another wallet that also follows that standard, it's going to plant the seed, it's going to create the master key, which is the root. It's then going to look on the 44th branch. It's going to look on the zero sub branch for your first account. It's going to look on the zero sub branch of that for receive addresses. And it's going to look at the first address or zero address hanging off that branch, derive the key and address. And it's going to look on the blockchain to see if there is some money stored or has ever been a transaction stored. And if it does find money, it will then start importing all of the addresses off that branch until it finds an empty gap called the gap limit, which tells it that you haven't gotten that far in your wallet, and you haven't used the last 20 addresses, 20 is the common gap limit. So that's what the derivation path is. It's a map that allows you to traverse the tree to find which branch your keys are on now. Unfortunately, that derivation path is not stored in the seed. This is one of the design weaknesses of the BIP 39 mnemonic phrase standard. And so the mnemonic phrase itself, the 12 to 24 words, doesn't contain a map of where on the tree these keys will be. And that is under the assumption that everybody will use the 44 standard branch and then put sub accounts there for different currencies, different accounts, et cetera, et cetera. And the 44 standard also allows for multiple different currencies. So there's a different branch for Bitcoin and a different branch for Ethereum and a different branch for Litecoin. And basically any type of cryptocurrency or blockchain that can support mnemonic phrases derived under this standard has a branch that it uses. So you can have a single mnemonic phrase that has branches for all of your cryptocurrencies and can generate billions of keys for you with billions of addresses so you can store your funds. Now, if you don't know what derivation path your wallet is using, one of the ways you can find it is from a website that collects that information, which is really great. It's called walletsrecovery.org. Wallets, plural, recovery, all one word, walletsrecovery.org. I'll put the link in the description. And walletsrecovery.org has a list of all of the derivation paths used by the most common wallets and a guide to help you find them. In fact, I'm working on a mechanism to help us search those branches. And so that may be a way for us to make it easier for newbies. If you do not know the derivation path of your wallet, then the next best thing you can do is write down what wallet model brand make if you like and what version. So you could write, for example, Electrum 3.38. And if that's the wallet that you were using when you put the funds on that mnemonic phrase, then we can then later perhaps help you by finding, oh, what derivation path did Electrum use in version 3.38? What derivation path did Koinoemi or Blockstream Green or BRD or whatever use on that specific version? So write down the wallet and version in order to be able to then find that. And you will discover from time to time that when you move your mnemonic phrase or copy your mnemonic phrase and initialize it in another wallet or another software system for your hardware wallet, that it will appear to be empty. And don't fret, your money's still there. It's just on a different branch than the one your wallet is looking for. And that causes a lot of confusion to newbies, but it's easily fixable as long as we find where that mnemonic phrase was last used.