Securities are a collective term for a variety of economic rights and interests certificates, and also refer to specialized types of products. They are legal certificates used to prove certain specific rights and interests enjoyed by the ticket holder. It mainly includes capital securities, currency securities and commodity securities. Securities in a narrow sense mainly refer to securities products in the securities market, including equity market products such as stocks, debt market products such as bonds, and derivative market products such as stock futures, options, interest rate futures, etc. The discipline system of securities science is an organic system composed of various branches of disciplines that study the behavioral characteristics and operating rules of the securities market from different angles. It mainly includes two major research fields: traditional securities theory and evolutionary securities theory.

Virtual capital is capital that is independent of actual capital movements, exists in the form of securities, and can bring a certain amount of income to the holder on a regular basis, such as banknotes, promissory notes, bills of exchange, stocks, Public bonds, real estate mortgages, etc. Virtual capital was created with the emergence of loan capital. It grew on the basis of loan capital and became a special investment field of loan capital.