That's correct, my friend. In Bitcoin, a digital signature is used to verify that a transaction is being authorized by the rightful owner of the Bitcoin funds. Each Bitcoin address corresponds to a single private key, and every time a transaction is sent from that address, it must be signed using the private key that corresponds to that address. The digital signature serves as proof that the transaction was authorized by the rightful owner of the funds associated with that address.

In other words, each Bitcoin address corresponds to one unique private key, and each private key can produce one and only one digital signature for each transaction that it authorizes. This ensures that only the owner of the Bitcoin funds associated with a particular address can authorize transactions from that address, adding an important layer of security to the Bitcoin system.