<human>:  I have a question about a financial instrument called a Credit default swap. What is it?
<bot>: A credit default swap is a financial instrument that allows a party to insure against the default of another party. It is a type of derivative contract that is used to transfer the risk of default from one party to another. The party that is insuring against default is called the "protection buyer" and the party that is insuring against default is called the "protection seller."