concept pubkey script in category bitcoin

This is an excerpt from Manning's book Grokking Bitcoin. Login to get full access to this book.

I haven’t been totally honest about what a transaction contains. A transaction’s output doesn’t contain a PKH, but part of a small computer program that contains a PKH. This part of the program is called a pubkey script. The input that spends the output contains the other part of this program. This other part, the signature and the public key in John’s transaction, is called a signature script (figure 5.11).

Figure 5.11. The signature script is the first part of a program. The pubkey script in the spent output is the second part. If the complete program results in OK, then the payment is authorized to spend the output.

Figure 10.5. Signing the first input. You prepare by copying the pubkey script to the signature script.

The signature scripts of all inputs are empty, but you copy the pubkey script of the spent output and insert it into the signature script of the spending input. You then create the signature for the first input and move on to sign the second input (figure 10.6).

The pubkey script for this output is