diff --git a/ch01.asciidoc b/ch01.asciidoc index 63578911..746128a5 100644 --- a/ch01.asciidoc +++ b/ch01.asciidoc @@ -117,13 +117,13 @@ Third-party API client:: ((("third-party API clients")))A third-party API client Combining these categorizations, many bitcoin wallets fall into a few groups, with the three most common being desktop full client, mobile lightweight wallet, and web third-party wallet. The lines between different categories are often blurry, as many wallets run on multiple platforms and can interact with the network in different ways. -For the purposes of this book, we will be demonstrating the use of a variety of downloadable bitcoin clients, from the reference implementation (Bitcoin Core) to mobile and web wallets. Some of the examples will require the use of Bitcoin Core, which, in addition to being a full client, also exposes APIs to the wallet, network, and transaction services. If you are planning to explore the programmatic interfaces into the bitcoin system, you will need to run Bitcoin Core, or one of the alternative clients (see <>).((("", startref="GSwallet01")))((("", startref="Wselect01"))) +For the purposes of this book, we will be demonstrating the use of a variety of downloadable bitcoin clients, from the reference implementation (Bitcoin Core) to mobile and web wallets. Some of the examples will require the use of Bitcoin Core, which, in addition to being a full client, also exposes APIs to the wallet, network, and transaction services. If you are planning to explore the programmatic interfaces into the bitcoin system, you will need to run Bitcoin Core, or one of the alternative clients.((("", startref="GSwallet01")))((("", startref="Wselect01"))) ==== Quick Start -((("getting started", "quick start example", id="GSquick01")))((("wallets", "quick start example", id="Wquick01")))((("use cases", "buying coffee", id="aliceone")))Alice, who we introduced in <>, is not a technical user and only recently heard about bitcoin from her friend Joe. While at a party, Joe is once again enthusiastically explaining bitcoin to all around him and is offering a demonstration. Intrigued, Alice asks how she can get started with bitcoin. Joe says that a mobile wallet is best for new users and he recommends a few of his favorite wallets. Alice downloads "Bluewallet" for Android and installs it on her phone. +((("getting started", "quick start example", id="GSquick01")))((("wallets", "quick start example", id="Wquick01")))((("use cases", "buying coffee", id="aliceone")))Alice, who we introduced in <>, is not a technical user and only recently heard about bitcoin from her friend Joe. While at a party, Joe is once again enthusiastically explaining bitcoin to all around him and is offering a demonstration. Intrigued, Alice asks how she can get started with bitcoin. Joe says that a mobile wallet is best for new users and he recommends a few of his favorite wallets. Alice downloads "Bluewallet" (available for iOS and Android) and installs it on her phone. -When Alice runs Bluewallet for the first time, she chooses the option to create a new Bitcoin wallet, and takes a moment **away from Joe and all other parties** to write down a secret mnemonic phrase _in order_ on a piece of paper. As explained by the mobile wallet and by Joe earlier, the mnemonic phrase allows Alice to restore her wallet in case she loses her mobile device and grants her access to her funds on another device. After creating her wallet and securing her mnemonic phrase, Alice can tap on her wallet to see her bitcoin amount, transaction history, as well as two buttons that allow her to either _receive_ or _send_ bitcoin, shown in <>. +When Alice runs her wallet application for the first time, she chooses the option to create a new Bitcoin wallet, and takes a moment **away from Joe and all other parties** to write down a secret mnemonic phrase _in order_ on a piece of paper. As explained by the mobile wallet and by Joe earlier, the mnemonic phrase allows Alice to restore her wallet in case she loses her mobile device and grants her access to her funds on another device. After creating her wallet and securing her mnemonic phrase, Alice can tap on her wallet to see her bitcoin amount, transaction history, as well as two buttons that allow her to either _receive_ or _send_ bitcoin, shown in <>. ==== Mnemonic Words @@ -145,10 +145,11 @@ Once Alice has recorded the mnemonic phrase, she should plan to store each copy ==== Never attempt a "DIY" security scheme that deviates in any way from the best practice recommendation in <>. Do not cut your mnemonic in half, make screenshots, store on USB drives, email or cloud drives, encrypt it, or try any other non-standard method. You will tip the balance in such a way as to risk permanent loss or theft. Many people have lost funds, not from theft but because they tried a non-standard solution without having the expertise to balance the risks involved. The best practice recommendation is carefully balanced by experts and suitable for the vast majority of users. ==== - +**** [[bluewallet-welcome]] .The Bluewallet Mobile Wallet image::images/bw_0101.png["BluewalletWelcome"] +**** ((("addresses", "bitcoin wallet quick start example")))((("QR codes", "bitcoin wallet quick start example")))((("addresses", see="also keys and addresses"))) The main wallet view displays the bitcoin amount, transaction history, and _Receive_ and _Send_ buttons. In addition, many wallets feature the ability to purchase Bitcoin directly through an exchange or similar service where you can offer fiat money in return for cryptocurrency, which is done by <> and selling to the wallet user at or above this price. The _Buy Bitcoin_ button would allow Alice to purchase Bitcoin in this fashion. @@ -161,7 +162,6 @@ Alice uses the _Receive_ button, which displays a QR code along with a bitcoin a ((("addresses", "security of")))((("security", "bitcoin addresses")))Bitcoin addresses start with 1, 3, or bc1. Like email addresses, they can be shared with other bitcoin users who can use them to send bitcoin directly to your wallet. There is nothing sensitive, from a security perspective, about the bitcoin address. It can be posted anywhere without risking the security of the account. Unlike email addresses, you can create new addresses as often as you like, all of which will direct funds to your wallet. In fact, many modern wallets automatically create a new address for every transaction to maximize privacy. A wallet is simply a collection of addresses and the keys that unlock the funds within. ==== -Alice is now ready to receive funds. Her wallet application randomly generated a private key together with its corresponding bitcoin address. At this point, her bitcoin address is not known to the bitcoin network or "registered" with any part of the bitcoin system. Her bitcoin address is simply a number that corresponds to a key that she can use to control access to the funds. It was generated independently by her wallet without reference or registration with any service. In fact, in most wallets, there is no association between the bitcoin address and any externally identifiable information including the user's identity. Until the moment this address is referenced as the recipient of value in a transaction posted on the bitcoin ledger, the bitcoin address is simply part of the vast number of possible addresses that are valid in bitcoin. Only once it has been associated with a transaction does it become part of the known addresses in the network. [[getting_first_bitcoin]] ==== Getting Her First Bitcoin @@ -201,7 +201,6 @@ In addition to these various sites and applications, most bitcoin wallets will a [[sending_receiving]] ==== Sending and Receiving Bitcoin - ((("getting started", "sending and receiving bitcoin", id="GSsend01")))((("spending bitcoin", "bitcoin wallet quick start example")))((("spending bitcoin", see="also transactions")))Alice has decided to exchange $10 US dollars for bitcoin, so as not to risk too much money on this new technology. She gives Joe $10 in cash, opens her Bluewallet mobile wallet application, and selects Receive. This displays a QR code with Alice's first bitcoin address. Joe then selects Send on his Bluewallet smartphone wallet and is presented with a screen containing the following inputs: @@ -229,7 +228,7 @@ The price of bitcoin has changed a lot over time, and an incredible amount since .Bluewallet mobile bitcoin wallet send screen image::images/mbc2_0102.png["bluewallet mobile send screen"] -Joe then carefully checks to make sure he has entered the correct amount, because he is about to transmit money and mistakes are irreversible. After double-checking the address and amount, he presses Send to transmit the transaction. Joe's mobile bitcoin wallet constructs a transaction that assigns 0.10 BTC to the address provided by Alice, sourcing the funds from Joe's wallet and signing the transaction with Joe's private keys. This tells the bitcoin network that Joe has authorized a transfer of value to Alice's new address. As the transaction is transmitted via the peer-to-peer protocol, it quickly propagates across the bitcoin network. In less than a second, most of the well-connected nodes in the network receive the transaction and see Alice's address for the first time. +Using Bluewallet, Joe carefully checks to make sure he has entered the correct amount, because he is about to transmit money and mistakes are irreversible. For simplicity sake, we will assume that Joe does not pay any transaction fees. The purpose and setting of transaction fees are covered in subsequent chapters. After double-checking the address and amount, he presses _Send_ to transmit the transaction. Joe's mobile bitcoin wallet constructs a transaction that assigns 0.10 BTC to the address provided by Alice, sourcing the funds from Joe's wallet and signing the transaction with Joe's private keys. This tells the bitcoin network that Joe has authorized a transfer of value to Alice's new address. As the transaction is transmitted via the peer-to-peer protocol, it quickly propagates across the bitcoin network. In less than a second, most of the well-connected nodes in the network receive the transaction and see Alice's address for the first time. Meanwhile, Alice's wallet is constantly "listening" to published transactions on the bitcoin network, looking for any that match the addresses it contains. A few seconds after Joe's wallet transmits the transaction, Alice's wallet will indicate that it is receiving 0.10 BTC. @@ -238,9 +237,8 @@ Meanwhile, Alice's wallet is constantly "listening" to published transactions on Each bitcoin can be subdivided into 100 million units, each called a "satoshi" (singular) or "satoshis" (plural). Named for bitcoin's creator, the Satoshi is the smallest unit of bitcoin, equivalent to 0.00000001 BTC. ==== +[[confirmations]] .Confirmations -**** -((("getting started", "confirmations")))((("confirmations", "bitcoin wallet quick start example")))((("confirmations", see="also mining and consensus; transactions")))((("clearing", seealso="confirmations")))At first, Alice's wallet will show the transaction from Joe as "Unconfirmed." This means that the transaction has been propagated to the network but has not yet been recorded in the bitcoin transaction ledger, known as the blockchain. To be confirmed, a transaction must be included in a block and added to the blockchain, which happens every 10 minutes, on average. In traditional financial terms this is known as _clearing_. For more details on propagation, validation, and clearing (confirmation) of bitcoin transactions, see <>. -**** +((("getting started", "confirmations")))((("confirmations", "bitcoin wallet quick start example")))((("confirmations", see="also mining and consensus; transactions")))((("clearing", seealso="confirmations")))At first, Alice's wallet will show the transaction from Joe as "Unconfirmed." This means that the transaction has been propagated to the network but has not yet been recorded in the bitcoin transaction ledger, known as the blockchain. To be confirmed, a transaction must be included in a block and added to the blockchain, which happens every 10 minutes, on average. In traditional financial terms this is known as _clearing_. This book will cover in detail the propagation, validation, and clearing (or confirmation) of bitcoin transactions. Alice is now the proud owner of 0.10 BTC that she can spend. In the next chapter we will look at her first purchase with bitcoin, and examine the underlying transaction and propagation technologies in more detail.((("", startref="BCbasic01")))((("use cases", "buying coffee", startref="aliceone"))) diff --git a/images/ew_0101.png b/images/ew_0101.png new file mode 100644 index 00000000..3332afae Binary files /dev/null and b/images/ew_0101.png differ