Merge pull request #75 from deadmanoz/content-fixes-and-improvements

Content fixes and improvements for transactions module

Author: jrakibi

decoding/endianness.mdx

@@ -74,7 +74,8 @@ Big-endian is considered more "human-readable" because the data is stored in the
 
 ## 2. Little-Endian
 
-Little-endian stores the **least significant byte** first. This might feel counterintuitive to humans but is more efficient for modern processors.
+Little-endian stores the **least significant byte** first. It might feel counterintuitive to humans but little-endian is widely used in modern processors,
+particularly in the x86 architecture family, largely due to historical decisions.
 
 Using the same number **12345678** (`0x00BC614E`), here's how it looks in **little-endian**:
 

decoding/fee-calculation.mdx

@@ -70,9 +70,9 @@ Without fees, miners would have no reason to include transactions in their block
 
 ### How Miners Select Transactions ?
 
-Miners receive two types of rewards for securing the network:
+Miners receive two types of payment for securing the network:
 
-1. **Block Reward**
+1. **Block Subsidy**
 2. **Transaction Fees**
 
 <div className="dark:hidden w-full rounded-lg">
@@ -96,7 +96,7 @@ A miner who mines a block will have revenue as:
     $$Revenue = Tx\ Fees + Block\ Subsidy$$
 </div>
 
-To maximize their revenue, miners prioritize transactions that pay higher fees. The way they determine which transactions pay more will be covered in the next topic when we discuss fee rates.
+To maximize their revenue, miners prioritize transactions that pay higher fees. The way they determine which transactions pay more will be covered in the [Fee Rate](/decoding/fee-rate) topic.
 
 For now, understand that:
 
@@ -127,7 +127,7 @@ While miners can choose which transactions to include based on fees, there's act
 This is called the **minimum relay fee**.
 
 -   It's the minimum fee required for nodes to relay and accept a transaction
--   Default is typically 1 sat/vbyte (we'll explain this unit sat/vbyte in the next topic)
+-   Default is typically 1 sat/vbyte (we'll explain this unit sat/vbyte in the [Transaction Weight](/decoding/transaction-weight) topic)
 -   Transactions below this threshold will be rejected by nodes
 -   Helps prevent spam and DoS attacks on the network
 

decoding/inputs-prev-txid.mdx

@@ -45,7 +45,6 @@ The txid uses Bitcoin's internal byte order (little-endian). Let's examine this
 display_txid = "5e6e1a9b4ce3f9f39467d7129e3ecfbe6c81c08dd377aac666fedc9a758fe614"
 
 # Internal order (how it appears in raw transaction)
-
 internal_txid = "14e68f759adcfe66c6aa77d38dc0816cbecf3e9e12d76794f3f9e34c9b1a6e5e"`}
 language="python"
 />
@@ -138,7 +137,12 @@ The TXID is created differently depending on the transaction type:
 This difference in segwit transactions was intentionally designed to prevent transaction malleability, as signatures are no longer part of the TXID calculation.
 
 <ExpandableAlert title="Historical Note" type="info">
-    There was a unique situation in Bitcoin's history where duplicate TXIDs occurred in blocks 91,722 and 91,880. As a result, BIP 30 was implemented to prevent blocks from containing duplicate TXIDs, and BIP 34 was introduced to require coinbase transactions to include block height in their data.
+    Duplicate TXID: `e3bf3d07d4b0375638d5f1db5255fe07ba2c4cb067cd81b84ee974b6585fb468`
+
+    There was a unique situation in Bitcoin's history where the same TXID (above) occurred in multiple blocks:
+    <a href="https://mempool.space/block/00000000000271a2dc26e7667f8419f2e15416dc6955e5a6c6cdf3f2574dd08e" target="_blank" rel="noopener noreferrer">91,722</a> and
+    <a href="https://mempool.space/block/00000000000743f190a18c5577a3c2d2a1f610ae9601ac046a38084ccb7cd721" target="_blank" rel="noopener noreferrer">91,880</a>.
+    As a result, BIP 30 was implemented to prevent blocks from containing duplicate TXIDs, and BIP 34 was introduced to require coinbase transactions to include block height in their data.
 </ExpandableAlert>
 
 ## Implementation Details

decoding/inputs-scriptsig.mdx

@@ -59,7 +59,7 @@ Let's break down the highlighted hex string from our transaction:
                 </td>
                 <td className="px-6 py-4">1 byte</td>
                 <td className="px-6 py-4">
-                    Script length in hex (72 bytes in decimal)
+                    Signature length in hex (72 bytes in decimal)
                 </td>
             </tr>
             <tr className="hover:bg-gray-100 dark:hover:bg-gray-800">

decoding/inputs-scriptsigsize.mdx

@@ -49,8 +49,8 @@ Like the input count, the ScriptSig size uses varint encoding:
 | 2³² to 2⁶⁴-1  | 0x100000000 to 0xffffffffffffffff | 9          | `0xff` followed by uint64_t |
 
 <ExpandableAlert title="Note" type="info">
-    Most ScriptSig sizes are small enough to fit in a single byte, as they
-    typically contain just a signature and public key.
+    Most ScriptSig sizes are small enough to fit in a single byte, as the ScriptSig
+    typically contains just a signature and public key that combined are less than 253 bytes in size.
 </ExpandableAlert>
 
 ## Implementation Example

decoding/inputs-sequence.mdx

@@ -131,8 +131,8 @@ Here's how you might parse a transaction input's sequence number:
 ## 3- Historical Context
 
 <ExpandableAlert title="Original Design" type="info">
-    Satoshi originally designed the sequence number for "high-frequency trades"
-    - a way to update transactions before they were mined. The idea was to
+    Satoshi originally designed the sequence number for "high-frequency trades" -
+    a way to update transactions before they were mined. The idea was to
     create payment channels between parties, where each new payment would
     increment the sequence number. However, this design was vulnerable to miner
     manipulation and was later replaced by better payment channel designs like
@@ -155,8 +155,8 @@ BIP 68 introduced relative timelocks using sequence numbers below 0x80000000. Th
     return sequence < 0xf0000000
 
 def is_relative_timelock(sequence: int) -> bool:
-"""Check if relative timelock is enabled"""
-return sequence < 0x80000000`}
+    """Check if relative timelock is enabled"""
+    return sequence < 0x80000000`}
 language="python"
 />
 

decoding/outputs-amount.mdx

@@ -98,8 +98,8 @@ Here's a helpful function for converting between BTC and satoshis:
     return int(btc * 100_000_000)
 
 def satoshis_to_btc(sats: int) -> float:
-"""Convert satoshi amount to BTC"""
-return sats / 100_000_000`}
+    """Convert satoshi amount to BTC"""
+    return sats / 100_000_000`}
 language="python"
 />
 

decoding/transaction-creation.mdx

@@ -144,4 +144,4 @@ In this example:
 ### Final Step: Signing the Transaction
 
 The transaction structure is now complete but not yet valid. Alice must sign it to prove she owns the inputs.
-The signing process will be covered in detail in the next topic.
+The signing process will be covered in detail in the [Signing Transactions](/decoding/transaction-signing) topic.

decoding/transaction-signing-01.mdx

@@ -130,15 +130,15 @@ Two essential encoding functions:
     return value.to_bytes(length, 'little')
 
 def varint(n: int) -> bytes:
-"""Encode an integer as a variable length integer"""
-if n < 0xfd:
-return bytes([n])
-elif n <= 0xffff:
-return b'\\xfd' + n.to_bytes(2, 'little')
-elif n <= 0xffffffff:
-return b'\\xfe' + n.to_bytes(4, 'little')
-else:
-return b'\\xff' + n.to_bytes(8, 'little')`}
+    """Encode an integer as a variable length integer"""
+    if n < 0xfd:
+        return bytes([n])
+    elif n <= 0xffff:
+        return b'\\xfd' + n.to_bytes(2, 'little')
+    elif n <= 0xffffffff:
+        return b'\\xfe' + n.to_bytes(4, 'little')
+    else:
+        return b'\\xff' + n.to_bytes(8, 'little')`}
 language="python"
 />
 

decoding/transaction-signing-03.mdx

@@ -74,7 +74,7 @@ For our test vector:
     - `76`: OP_DUP 
     - `a9`: OP_HASH160 
     - `14`: Push 20 bytes 
-    - `1d0f172a0ecb48aee1be1f2687d2963ae33f71a1`: Public key hash from witness program 
+    - `1d0f172a0ecb48aee1be1f2687d2963ae33f71a1`: 20-byte public key hash from witness program
     - `88`: OP_EQUALVERIFY 
     - `ac`: OP_CHECKSIG
 </ExpandableAlert>