minor changes to Introduction & CH 1

00_0_Introduction.md

@@ -4,7 +4,7 @@ The ways that we make payments for goods and services has been changing dramatic
 
 These centralization risks were some of the prime catalysts behind the creation of cryptocurrencies, the first and most successful of which is Bitcoin. Bitcoin offers pseudonymity, it makes it difficult to correlate transactions, and it makes censorship by individual entities all but impossible. These advantages have made it one of the quickest growing currencies in the world. That growth in turn has made Bitcoin into a going concern among entrepreneurs and developers, eager to create new services for the Bitcoin community.
 
-If you're one of those entrepreneurs or developers, then this book is for you, because it's all about learning to program Bitcoin. It's an introductory book that explains all the nuances and features of Bitcoin as it goes. It also takes a very specific tack, by offering lessons in how to work _directly_ with Bitcoin Core and with the c-lightning server using their RPG interfaces. 
+If you're one of those entrepreneurs or developers, then this book is for you, because it's all about learning to program Bitcoin. It's an introductory book that explains all the nuances and features of Bitcoin as it goes. It also takes a very specific tack, by offering lessons in how to work _directly_ with Bitcoin Core and with the c-lightning server using their RPC interfaces.
 
 Why not use some of the more fully featured libraries found in various programming languages? Why not create your own from scratch? It's because working with cryptocurrency is dangerous. There are no safety nets. If you accidentally overpay your fees or lose a signing key or create an invalid transaction or make any number of potential mistakes, then your cryptocurrency will been gone forever. Much of that responsibility will, of course, lie with you as a cryptocurrency programmer, but it can be minimized by working with the most robust, secure, and safe cryptocurrency interfaces around, the ones created by the cryptocurrency programming teams themselves: ``bitcoind`` and ``lightningd``.
 
@@ -21,7 +21,7 @@ This book is broadly divided into the following sections:
    * **Part Five: Using Lightning-CLI** - Using the Lightning-CLI for creating transactions.
    * **Part Six: Programming with RPC** - Accessing RPC from C and other languages.
    * **Appendices** - Utilizing less common Bitcoin setups.
-   
+
 ## What's Next?
 
 Learn the basics of Bitcoin in [Chapter One: Introducing Bitcoin](01_0_Introducing_Bitcoin.md).

01_0_Introducing_Bitcoin.md

@@ -15,12 +15,12 @@ Supporting objectives include the ability to:
    * Understand What Blockchain Transactions Are
    * Understand What Blockchain Is
    * Understand What Lightning Is
-   
+
 ## About Bitcoin
 
 Bitcoin is a programmatic system that allows for the transfer of the bitcoin currency. It is enabled by a decentralized, peer-to-peer system of nodes, which include full nodes, wallets, and miners. Working together, they ensure that bitcoin transactions are fast and non-repudiable. Thanks to the decentralized nature of the system, these transactions are also censor-resistant and can provide other advantages such as pseudonymity and non-correlation if used well.
 
-Obviously, Bitcoin is the heart of this book, but it's also the originator of many other systems, including blockchains and Lightning, which are both detailed in this tutorial, and many other cryptocurrencies such as Ethereum and Litecoins, which are not. 
+Obviously, Bitcoin is the heart of this book, but it's also the originator of many other systems, including blockchains and Lightning, which are both detailed in this tutorial, and many other cryptocurrencies such as Ethereum and Litecoins, which are not.
 
 **_How Are Coins Transferred?_** Bitcoin currency isn't physical coins. Instead it's an endless series of ownership reassignments. When one person sends coins to another, that transfer is stored as a transaction. It's the transaction that actually records the ownership of the money, not any token local to the owner's wallet or their machine.
 
@@ -54,7 +54,7 @@ It's important to Bitcoin (and to most blockchain systems) because it's the basi
 
 **_What Is a Signature?_** A message (or more commonly, a hash of a message) can be signed with a private key, creating a signature. Anyone with the corresponding public key can then validate the signature, which verifies that the signer owns the private key associated with the public key in question. _SegWit_ is a specific format for storing a signature on the Bitcoin network that we'll meet down the line.
 
-**_What Is a Hash Function?_** A hash function is an algorithm frequently used with cryptography. It's a way to map a large, arbitrary amount of data to a small, fixed amount of data. Hash functions used in cryptography are one-way and collision-resistant, meaning that a hash can reliably be linked to the original data, but the original data can not be regenerated from the hash. Hashes thus allow the transmission of small amounts of data to represent large amounts of data, which can be important for efficiency and storage requirements. 
+**_What Is a Hash Function?_** A hash function is an algorithm frequently used with cryptography. It's a way to map a large, arbitrary amount of data to a small, fixed amount of data. Hash functions used in cryptography are one-way and collision-resistant, meaning that a hash can reliably be linked to the original data, but the original data can not be regenerated from the hash. Hashes thus allow the transmission of small amounts of data to represent large amounts of data, which can be important for efficiency and storage requirements.
 
 Bitcoin takes advantage of a hash's ability to disguise the original data, which allows concealment of a user's actual public key, making transactions resistant to quantum computing.
 
@@ -72,9 +72,9 @@ ECC does not receive much attention in this tutorial. That's because this tutori
 
 Any line that intersects an elliptic curve will do so at either 1 or 3 points ... and that's the basis of elliptic-curve cryptopgrahy.
 
-**_What are Finite Fields?_** A finite field is a finite set of numbers, where all addition, subtraction, multiplication, and division is defined so that it results in other numbers also in the same finite field. One simple way to create a finite field is through the use of a modulo function. 
+**_What are Finite Fields?_** A finite field is a finite set of numbers, where all addition, subtraction, multiplication, and division is defined so that it results in other numbers also in the same finite field. One simple way to create a finite field is through the use of a modulo function.
 
-**_How is an Elliptic Curve Defined Over a Finite Field?_** An ellipitic curve defined over a finite field has all of the points on its curve drawn from a specific finite field. This takes the form: `y`<sup>`2`</sup> `% field-size = (x`<sup>`3`</sup>` + ax + b) % field-size` The finite field used for secp256k1 is `2`<sup>`256`</sup>` - 2`<sup>`32`</sup>` - 2`<sup>`9`</sup>` - 2`<sup>`8`</sup>` - 2`<sup>`7`</sup>` - 2`<sup>`6`</sup>` - 2`<sup>`4`</sup>` - `<sup>`1`</sup>`. 
+**_How is an Elliptic Curve Defined Over a Finite Field?_** An ellipitic curve defined over a finite field has all of the points on its curve drawn from a specific finite field. This takes the form: `y`<sup>`2`</sup> `% field-size = (x`<sup>`3`</sup>` + ax + b) % field-size` The finite field used for secp256k1 is `2`<sup>`256`</sup>` - 2`<sup>`32`</sup>` - 2`<sup>`9`</sup>` - 2`<sup>`8`</sup>` - 2`<sup>`7`</sup>` - 2`<sup>`6`</sup>` - 2`<sup>`4`</sup>` - 1`.
 
 **_How Are Elliptic Curves Used in Cryptography?_** In elliptic-curve cryptography, a user selects a very large (256-bit) number as his private key. He then adds a set base point on the curve to itself that many times. (In secp256k1, the base point is `G = 04 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798 483ADA77 26A3C465 5DA4FBFC 0E1108A8 FD17B448 A6855419 9C47D08F FB10D4B8`, which prefixes the two parts of the tuple with an `04` to say that the data point is in uncompressed form. If you prefer a straight geometric definition, it's the point "0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798,0x483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8") The resultant number is the public key. Various mathematical formula can then be used to prove ownership of the public key, given the private key. As with any cryptographic function, this one is a trap door: it's easy to go from private key to public key and largely impossible to go from public key to private key.
 
@@ -84,21 +84,21 @@ This particular methodology also explains why finite fields are used in elliptic
 
 ### ECC - In Short
 
-One way to think of public-key cryptography is: _a way to enable public-key cryptography that uses very small keys and very obscure math._
+One way to think of ECC is: _a way to enable public-key cryptography that uses very small keys and very obscure math._
 
 ## About Blockchains
 
-Blockchain is the generalization of the methodology used by Bitcoin to create a distributed global ledger. Bitcoin is a blockchain as are any number of alt-coins, each of which lives on its own networks and writes to its own chain. Sidechains like Liquid are blockchains too. Blockchains don't even need to have anything to do with finances. For example, there have been many discussions of using blockchains to protect self-sovereign identities.
+Blockchain is the generalization of the methodology used by Bitcoin to create a distributed global ledger. Bitcoin is a blockchain as are any number of alt-coins, each of which lives on its own network and writes to its own chain. Sidechains like Liquid are blockchains too. Blockchains don't even need to have anything to do with finances. For example, there have been many discussions of using blockchains to protect self-sovereign identities.
 
-Though you need to understand the basics of how a blockchain works to understand how transactions work in Bitcoin, you won't need to go any further than that. Because blockchains have become a wide category of technology, those basic concepts are likely to be applicable to many other projects in this growing technology sector. The specific programming commands learned in this book will not be, however, as they're fairly specific to Bitcoin (and Lightning). 
+Though you need to understand the basics of how a blockchain works to understand how transactions work in Bitcoin, you won't need to go any further than that. Because blockchains have become a wide category of technology, those basic concepts are likely to be applicable to many other projects in this growing technology sector. The specific programming commands learned in this book will not be, however, as they're fairly specific to Bitcoin (and Lightning).
 
-**_Why Is It Called a Chain?_** Each block in the blockchain stores a hash of the block before it. This links the current block all the way back to the original "genesis block" through an unbroken chain. It's a way to create absolute order among possibly conflicting data. This also provides the security of blockchain, because each block stacked atop an old one makes it harder to recreate the old block due to the proof-of-work algorithms used in block creation. Once several blocks have been built atop a block in the chain, it's essentially irreversible. 
+**_Why Is It Called a Chain?_** Each block in the blockchain stores a hash of the block before it. This links the current block all the way back to the original "genesis block" through an unbroken chain. It's a way to create absolute order among possibly conflicting data. This also provides the security of blockchain, because each block is stacked atop an old one makes it harder to recreate the old block due to the proof-of-work algorithms used in block creation. Once several blocks have been built atop a block in the chain, it's essentially irreversible.
 
-**_What is a Fork?_** Occasionally two blocks are created around the same time. This temporarily creates a one-block fork, where either current block could be the "real" one. Every once in a while, a fork might expand to become two blocks, three blocks, or even four blocks long, but pretty quickly one side of the fork is determined to be the real one, and the other is "orphaned". This is part of the stochastic process of block creation, and demonstrates why several blocks must be built atop a block before it can be considered truly trustworthy and non-repudiable.
+**_What is a Fork?_** Occasionally two blocks are created around the same time. This temporarily creates a one-block fork, where either if the current blocks could be the "real" one. Every once in a while, a fork might expand to become two blocks, three blocks, or even four blocks long, but pretty quickly one side of the fork is determined to be the real one, and the other is "orphaned". This is part of the stochastic process of block creation, and demonstrates why several blocks must be built atop a block before it can be considered truly trustworthy and non-repudiable.
 
 ### Blockchain — In Short
 
-One way to think of blockchain is: _a linked series of blocks of unchangeable data, going back in time_. Another way is: _a linked series of blocks that absolutely order data that could be conflicting_.
+One way to think of blockchain is: _a linked series of blocks of unchangeable data, going back in time_. Another way is: _a linked series of blocks to absolutely order data that could be conflicting_.
 
 ## Is Blockchain Right for Me?
 
@@ -115,7 +115,7 @@ Blockchains probably _will_ be helpful if:
     * And: Users want what's shared to be permanently recorded.
   * Users want fast transaction finality.
     * But: Users don't need instant transaction finality.
-    
+
 Blockchains probably _will not_ be helpful if:
 
   * Users are trusted:
@@ -128,8 +128,8 @@ Blockchains probably _will not_ be helpful if:
     * Unless: A methodology for cryptographic secrecy is carefully considered, analyzed, and tested.
   * Users need instant transaction finality.
     * e.g.: in less than 10 minutes on a Bitcoin-like network, in less than 2.5 minutes on a Litecoin-like network, in less than 15 seconds on an Ethereum-like network
-  
-Do note that there may still be solutions for some of these situations within the Bitcoin ecosystem. For example, payment channels are rapidly addressing questions of liquidity and payment finality. 
+
+Do note that there may still be solutions for some of these situations within the Bitcoin ecosystem. For example, payment channels are rapidly addressing questions of liquidity and payment finality.
 
 ## About Lightning
 
@@ -145,7 +145,7 @@ Unlike with Bitcoin, there are actually several variants of Lightning. This tuto
 
 **_What is a Lightning Network?_** Putting together a number of Lightning Channels creates the Lightning Network. This allows two users who have not created a channel between themselves to exchange bitcoins using Lightning: the protocol forms a chain of Channels between the two users, then exchanges the coins through the chain using time-locked transactions.
 
-**_What are the Advantages of Lightning?_** Lightning allows for faster transactions with lower fees. This creates the real possibility of bitcoin-funded micropayments. It also offers better privacy, since it's off-chain with only the first and last states of the transaction being written to the immutable Bitcoin ledger. 
+**_What are the Advantages of Lightning?_** Lightning allows for faster transactions with lower fees. This creates the real possibility of bitcoin-funded micropayments. It also offers better privacy, since it's off-chain with only the first and last states of the transaction being written to the immutable Bitcoin ledger.
 
 **_What are the Disadvantages of Lightning?_** Lightning is still a very new technology and hasn't been tested as thoroughly as Bitcoin. That's not just a question of the technological implementation, but also whether the design itself can be gamed in any unexpected ways.