The risk–return spectrum is the relationship between the amount of return gained on an investment and the amount of risk undertaken in that investment. The more return sought, the more risk that must be undertaken.

Credit is the trust which allows one party to provide money or resources to another party wherein the second party does not reimburse the first party immediately, but promises either to repay or return those resources at a later date. The resources provided by the first party can be either property, fulfillment of promises, or performances. In other words, credit is a method of making reciprocity formal, legally enforceable, and extensible to a large group of unrelated people.