Improved formatting to make sections cohere better.

01_0_Introducing_Bitcoin.md

@@ -34,7 +34,7 @@ However, the process of building these blocks is stochastic: it's somewhat rando
 
 Funds are further protected by the use of hashes. Public keys aren't actually stored in the blockchain, only public-key hashes are. This means that even if quantum computer were to come along, Bitcoin transactions would remain protected by this second level of cryptography.
 
-**How Are Transactions Created?** The heart of each Bitcoin transaction is a FORTH-like scripting language that is used to lock the transaction. To respend the money, the recipient provides specific information to the script that proves he's the intended recipient.
+**_How Are Transactions Created?_** The heart of each Bitcoin transaction is a FORTH-like scripting language that is used to lock the transaction. To respend the money, the recipient provides specific information to the script that proves he's the intended recipient.
 
 However, these Bitcoin scripts are the lowest level of Bitcoin functionality. Much Bitcoin work is done through the `bitcoind` Bitcoin daemon, which is controlled through RPC commands. Many people send those RPC commands through the `bitcoin-cli` program, which provides an even simpler interface. Non-programmers don't even worry about these minutia, but instead use programmed wallets with simpler interfaces.
 
@@ -48,21 +48,13 @@ Public-key cryptography is a mathematical system for protecting data and proving
 
 It's important to Bitcoin (and to most blockchain systems) because it's the basis of a lot of the cryptography that protects the cryptocurrency funds. A Bitcoin transaction is typically sent to an address that is a hashed public key. The recipient is then able to retrieve the money by revealing both the public key and the private key.
 
-### What Is a Public Key?
+**_What Is a Public Key?_** A public key is the key given out to other people. In a typical public-key system, a user generates a public key and a private key, then he gives the public key to all and sundry. Those recipients can encrypt information with the public key, but it can't be decrypted with the same public key because of the asymmetry of the key pair.
 
-A public key is the key given out to other people. In a typical public-key system, a user generates a public key and a private key, then he gives the public key to all and sundry. Those recipients can encrypt information with the public key, but it can't be decrypted with the same public key because of the asymmetry of the key pair.
+**_What Is a Private Key?_** A private key is linked to a public key in a key pair. In a typical public-key system, a user keeps his private key secure and uses it to decrypt messages that were encrypted with his public key in the process of being sent to him..
 
-### What Is a Private Key?
+**_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. 
 
-A private key is linked to a public key in a key pair. In a typical public-key system, a user keeps his private key secure and uses it to decrypt messages that were encrypted with his public key in the process of being sent to him..
-
-### 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. 
-
-### 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 very 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 very 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. 
 
 Hashes also disguise what the original data is, which in the case of Bitcoin allows the concealment of the actual public key, making transactions resistant to quantum computing.
 
@@ -93,13 +85,9 @@ Blockchain is the generalization of the methodology used by Bitcoin to create a
 
 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?
+**_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 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. 
 
-Each block in the blockchain stores a hash of the block before it. This links the current block all the way back 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. 
-
-### 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 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.
 
 ### Blockchain — In Short