The right of rescission is the legal right of a consumer to back out of a purchase within three business days without suffering a penalty. The right of rescission is attached to specific purchases made where contracts are involved and is controlled by federal and state laws. The period during which a right of rescission may be exercised is often called a "cooling off period" and is intended to allow a consumer to reevaluate their recent activity without the pressure of a looming and strident salesperson.
Note that in the case of an automobile loan, most states specify that the purchaser has voluntarily relinquished their right of rescission if they take physical possession of the automobile. The right of rescission does not apply to all loans, does not apply in all circumstances, and varies by jurisdiction. It is intended as a consumer protection.