Risk is the uncertainty between production purpose and labor result, which has two meanings: one definition emphasizes that risk is manifested as income uncertainty; Another definition emphasizes that risk is expressed by the uncertainty of cost or expense. If the uncertainty of income or cost is used to represent risk, it means that the result of risk may bring loss, profit or no loss or profit, which is a generalized risk. The owner's exercise of ownership should be regarded as management risk, and financial risk belongs to this category.

The uncertainty of risk shows that risk can only be expressed as loss, and there is no possibility of profit from risk, which belongs to narrow sense risk. Risk and income are in direct proportion, so radical investors tend to take high risks in order to get higher income, while cautious investors focus on security considerations.