 And on today's Down the Rabbit Hole segment, I want to talk about paper wallets. Now paper wallets are not simply things that you record on paper. I like recording things on paper. It's a convenient way to record something like a mnemonic phrase. And in fact, recording a mnemonic phrase on paper is one way to do a backup. It's not as good as recording it on steel, but it is one way of doing a backup and it's better than not doing a backup at all. But what I'm talking about when I say paper wallet is a technology that was introduced way in the beginning of Bitcoin, which is a single key paper wallet. This is where you record a private key and a corresponding Bitcoin address as QR codes that are printed out onto a piece of paper. That's what we call a paper wallet. And paper wallets were extremely popular in the early days of Bitcoin in 2013 and 2014. We didn't have mnemonic phrases. We didn't yet have deployed wallets with BIP32 hierarchical deterministic wallets where we could generate as many addresses and keys as we wanted to. We didn't have easy backups with mnemonic phrases. So how did we store long-term amounts of crypto in cold storage? We used paper wallets. In fact, I built a company that would send out a kit that you could use to build pretty paper wallets with nice security features on your own computer with a bootable operating system. And at the time, that was okay. Well, it's not okay anymore. And even though I liked paper wallets and I used paper wallets and I even sold kits for paper wallets, I have spent the last five years telling people not to use paper wallets. Paper wallets are obsolete technology. Single key paper wallets have nuanced pitfalls that can cause newbies to lose money. In order to use them, you need a degree of technical sophistication where you can very, very easily exceed your level of technical knowledge and fall into obvious mistakes that cause you to lose money. It requires a knowledge of operating systems, information security and operational security practices that most people can't execute. And there's no need to go through all that because we now have purpose-built mini computers called hardware wallets with a minimum set of hardware and software that can produce incredibly flexible multi-currency, multi-account, hierarchical deterministic wallets with the ability to generate a new address for every transaction and even for multiple different cryptocurrencies and back all of that up on 12 English words that you can record on paper, steel or any other way you want. And that is the state of the art for key management, key generation, key storage, transaction signing and backup. Anything you could do with a single key paper wallet, you can do better with a mnemonic phrase. And it's not just the paper wallet. As a storage mechanism, it's fine. The problems come into how do you generate these things? What software and what hardware do you use to generate the paper wallets in the first place? And effectively the answer to that is a hardware wallet, only one not built by security professionals to exacting specifications and a minimum set of hardware and software, one built by you on an old Dell computer, a self-installed version of Linux that you somehow procured from the internet without getting atrocious and then you send all of that to a printer that you hope will not maintain a memory image of that printout. And then in order to spend, you have to repeat this process and sign a transaction by properly sweeping all of the UTXO and not creating extraneous change and then sign that transaction on a device that again isn't a hardware wallet but is in fact a laptop that you constructed hoping it is properly air-gapped, properly configured and didn't get any Trojan software installed even though it contains a myriad of applications and you have not got the skills to audit it properly, I'm sorry to say. So DIY hardware wallets are needed in order to use paper wallets and that's why they are very, very dangerous for newbies. Do not use single key paper wallets. Simply don't. There is no conceivable reason why you can't do the same or better by buying a properly designed hardware wallet that has been audited. If you're really paranoid, get one that's open source. Get one that supports air-gapped operation. Get one that allows you to introduce your own entropy. The cold card is a great example of that or get one of the other ones that are still much better than your DIY solution and before you jump in and say, yes, but what about if I use tails? No. Yes, but what about if I use the USB stick? No. Yes, but what about if I used AES-256, TrueCrypt and Veracrypt? No. And before you jump in and ask me, but what about any of the other myriad solutions? A mnemonic phrase generated by a purpose-built piece of hardware stored on a secure element in a purpose-built piece of hardware where you can sign transactions securely and confirm them on a screen that has no other purpose and no other software is always better than anything you can do. Don't use paper wallets. Thank you. What is the best way to get funds out of a paper wallet and move it to a hardware wallet? That's a great question. Many software companions that you can use with a hardware wallet have the ability to do what is known as a sweep. A sweep is the mechanism we use to clear funds out of a paper wallet. A sweep takes all of the UTXO, all of the funds from the paper wallet and in a single transaction without change transfers those funds to a destination address that belongs to your new wallet. You can enter your own destination address. You could do this on a software wallet or you could connect a hardware wallet to a variety of software wallets that have hardware wallet interfaces and ask it to sweep a paper wallet. So what you need to do is research which software wallets allow you to sweep a paper wallet either to an address of your choice so you can send it to an address that is controlled by your hardware wallet or can connect to a hardware wallet interface to get an address and sweep it into there. And that's how you move funds off a paper wallet. I hope you enjoyed that video. 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