1. Money other than the principal obtained from deposits and loans (different from "principal"). Theoretically speaking, interest refers to the value-added generated by monetary capital injected into the real economy and returned to the real economy. Interest is not so abstract. Generally speaking, it refers to the remuneration paid by the borrower (debtor) to the lender (creditor) for using the borrowed currency or capital. Also known as the symmetry between secondary gold and parent gold. The calculation formula of interest is: interest = principal × interest rate × deposit term (that is, term). Interest is the return that capital owners get by borrowing money. It comes from a part of profits formed by producers using these funds to perform their business functions. Refers to the added value brought by the injection and return of monetary funds to the real economic sector. The calculation formula is: interest = principal × interest rate× shelf life × 100%.
2. Classification of bank interest According to the nature of banking business, it can be divided into bank interest receivable and bank interest payable. Interest receivable refers to the remuneration obtained from the borrower when the bank issues funds to the borrower; It is the price that the borrower must pay for using the funds; This is also part of the bank's profits. Interest payable refers to the remuneration paid by banks to depositors by absorbing deposits; This is not only the price that banks must pay to absorb deposits, but also part of the cost of banks.
3. Theoretical basis Marx's political economy view Marxism believes that the essence of interest is a part of profit and a form of transformation of surplus value. Money itself cannot create money, nor will it increase in value. Functional capital can only create surplus value through the labor of employees in the production process by purchasing production materials and labor materials with money. Monetary capitalists and functional capitalists share surplus value because they own capital. Therefore, the separation of capital ownership and capital use right is the inherent premise of interest generation. Due to the characteristics of the reproduction process, the coexistence of capital surplus and capital shortage is the external condition for the production of benefits.
Money becomes capital when it is owned by capitalists and used as a means to exploit the surplus value of hired workers. Money performs the function of capital and obtains additional use value, that is, the ability to generate average profits. Driven by the interests of all capitalists who pursue surplus value, profits are transformed into average profits.