A contract between three parties, where one party, (called “the surety”), issues the bond on behalf of the second party (called the principal) and is responsible for the obligation of the second party, and the third party (called “the obligee”), which will receive the obligation of the second party.

Surety bonds are used to allure the “oblige” to contract with the principal, who is credible for contract completion, as guaranteed by the surety.
Bail bond is, for example, a type of surety bond.