From aca0196745c96bae4abb3b1c8324d875d70168d7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Erik=20Wahlstr=C3=B6m?= Date: Fri, 25 Apr 2014 11:37:29 +0200 Subject: [PATCH] typo fixes --- ch02.asciidoc | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/ch02.asciidoc b/ch02.asciidoc index 4be13ff7..2fe849f1 100644 --- a/ch02.asciidoc +++ b/ch02.asciidoc @@ -26,7 +26,7 @@ image::images/Bitcoin_Overview.png["Bitcoin Overview"] ==== Buying a cup of coffee -Alice, who we introduced in the previous chapter, is a new user who has just acquired her first bitcoin. In <>, Alice met with her frined Joe to exchange some cash for bitcoin. The transaction created by Joe, funded Alice's wallet with 0.10 BTC. Now Alice will make her first retail transaction, buying a cup of coffee at Bob's coffee shop in Palo Alto, California. Bob's coffee shop recently started accepting bitcoin payments, by adding a bitcoin option to his point-of-sale system (see <> for information on using bitcoin for merchants/retail). The prices at Bob's Cafe are listed in the local currency (US dollars) but at the register, customers have the option of paying in either dollars or bitcoin. Alice places her order for a cup of coffee and Bob enters the transaction at the register. The point-of-sale system will convert the total price from US dollars to bitcoins at the prevailing market rate and displays the prices in both currencies, as well as showing a QR code containing a _payment request_ for this transaction: +Alice, who we introduced in the previous chapter, is a new user who has just acquired her first bitcoin. In <>, Alice met with her friend Joe to exchange some cash for bitcoin. The transaction created by Joe, funded Alice's wallet with 0.10 BTC. Now Alice will make her first retail transaction, buying a cup of coffee at Bob's coffee shop in Palo Alto, California. Bob's coffee shop recently started accepting bitcoin payments, by adding a bitcoin option to his point-of-sale system (see <> for information on using bitcoin for merchants/retail). The prices at Bob's Cafe are listed in the local currency (US dollars) but at the register, customers have the option of paying in either dollars or bitcoin. Alice places her order for a cup of coffee and Bob enters the transaction at the register. The point-of-sale system will convert the total price from US dollars to bitcoins at the prevailing market rate and displays the prices in both currencies, as well as showing a QR code containing a _payment request_ for this transaction: .Displayed on Bob's cash register ---- @@ -75,7 +75,7 @@ The bitcoin network can transact in fractional values, e.g. from millibitcoins ( === Bitcoin Transactions -In simple terms, a transaction tells the network that the owner of a number bitcoins has authorized the transfer of some of those bitcoins to another owner. The new owner can now spend these bitcoins by creating another transaction that authorizes transfer to another owner, and so on, in a chain of ownership. +In simple terms, a transaction tells the network that the owner of a number of bitcoins has authorized the transfer of some of those bitcoins to another owner. The new owner can now spend these bitcoins by creating another transaction that authorizes transfer to another owner, and so on, in a chain of ownership. Transactions are like lines in a double-entry bookkeeping ledger. In simple terms, each transaction contains one or more "inputs", which are debits against a bitcoin account. On the other side of the transaction, there are one or more "outputs", which are credits added to a bitcoin account. The inputs and outputs (debits and credits) do not necessarily add up to the same amount. Instead, outputs add up to slightly less than inputs and the difference represents an implied "transaction fee", a small payment collected by the miner who includes the transaction in the ledger. @@ -166,7 +166,7 @@ As you can see, Alice's wallet contains enough bitcoins in a single unspent outp A transaction output is created in the form of a script, that creates an encumberance on the value and can only be redeemed by the introduction of a solution to the script. In simpler terms, Alice's transaction output will contain a script that says something like "This output is payable to whoever can present a signature from the key corresponding to Bob's public address". Since only Bob has the wallet with the keys corresponding to that address, only Bob's wallet can present such a signature to redeem this output. Alice will therefore "encumber" the output value with a demand for a signature from Bob. -This transaction will also include a second output, because Alice's funds are in a the form of a 0.10 BTC output, too much money for the 0.015 BTC cup of coffee. Alice will need 0.085 BTC in change. Alice's change payment is created _by Alice's wallet_ in the very same transaction as the payment to Bob. Essentially, Alice's wallet breaks her funds into two payments, one to Bob, one back to herself. She can then use the change output in a subsequent transaction, thus spending it later. +This transaction will also include a second output, because Alice's funds are in the form of a 0.10 BTC output, too much money for the 0.015 BTC cup of coffee. Alice will need 0.085 BTC in change. Alice's change payment is created _by Alice's wallet_ in the very same transaction as the payment to Bob. Essentially, Alice's wallet breaks her funds into two payments, one to Bob, one back to herself. She can then use the change output in a subsequent transaction, thus spending it later. Finally, for the transaction to be processed by the network in a timely fashion, Alice's wallet application will add a small fee. This is not explicit in the transaction, it is implied by the difference between inputs and outputs. If instead of taking 0.085 in change, Alice creates only 0.0845 as the second output, there will be 0.0005 BTC (half a millibitcoin) left over. The input's 0.10 BTC is not fully spent with the two outputs, as they will add up to less than 0.10. The resulting difference is the _transaction fee_ which is collected by the miner as a fee for including the transaction in a block and putting it on the blockchain ledger.