A banker or bank is a financial institution whose primary activity is to act as a payment agent for customers and to borrow and lend money. Engaging in the business of keeping money for savings and checking accounts or for exchange or for issuing loans and credit etc. Insurance, in law and economics, is a form of risk management primarily used to hedge against the risk of a contingent loss. Insurance is defined as the equitable transfer of the risk of a loss, from one entity to another, in exchange for a premium, and can be thought of a guaranteed small loss to prevent a large, possibly devastating loss. An insurer is a company selling the insurance. The insurance rate is a factor used to determine the amount, called the premium, to be charged for a certain amount of insurance coverage. Risk management, the practice of appraising and controlling risk, has evolved as a discrete field of study and practice.