# Gavin Andresen
# 2010-07-23 02:25:44
# https://bitcointalk.org/index.php?topic=535.msg5181#msg5181

TxIn: prev(82df...6428:1) means the second TxOut of transaction 82df...something...6428  (it abbreviates the full 256-bit transaction hash and starts counting at zero). @p{par}

To see that transaction: @p{brk}

Code:
gavin$ dbdump.py @p{--}transaction=82df...6428 @p{brk}
1 tx in, 2 out @p{brk}
['TxIn: prev(bfb0...cd16:1) pubkey: 17muZqKMEFqzefsqYhR9vqBjz1jNVcDcbh sig: 71:3044...0201 65:0480...af42'] @p{brk}
['TxOut: value: 0.05 pubkey: 1GVgigFDZ9pPLyYwxboEoaSDMDbsBQPVMx Script: DUP HASH160 20:a9f6...9268 EQUALVERIFY CHECKSIG', 'TxOut: value: 66.07 pubkey: 1LsvDRhoMmH5YeZDAxaP5rqwNTp3xFCF3Q Script: DUP HASH160 20:da0b...a345 EQUALVERIFY CHECKSIG'] @p{brk}

This looks like bitnickels coins coming out of the Bitcoin Faucet.  The transaction before THAT is: @p{brk}

Code:
gavin$ dbdump.py @p{--}transaction=bfb0...cd16 @p{brk}
1 tx in, 2 out @p{brk}
['TxIn: prev(b1dd...5cd9:1) pubkey: 1MQNsNwRHTu7MWPgFRGRRZfo58jU3RGxJv sig: 73:3046...8501 65:041b...6624'] @p{brk}
['TxOut: value: 0.05 pubkey: 1GVgigFDZ9pPLyYwxboEoaSDMDbsBQPVMx Script: DUP HASH160 20:a9f6...9268 EQUALVERIFY CHECKSIG', 'TxOut: value: 66.12 pubkey: 17muZqKMEFqzefsqYhR9vqBjz1jNVcDcbh Script: DUP HASH160 20:4a4e...e0c3 EQUALVERIFY CHECKSIG'] @p{brk}

 @p{brk}
To compute the net transaction value, just add up the values of all the TxOuts; they have to equal the sum of all the TxIns (well, unless there are @p{(link}transaction fees@p{link)}).  So for that first transaction, 66.07+0.05 = 66.12 (which is, indeed, bfb0...cd16:1) @p{brk}