warrants refer to the securities issued by the issuer of the underlying securities or a third party other than them, which stipulate that the holder has the right to buy or sell the underlying securities from the issuer at the agreed price within a specified period or a specific maturity date, or collect the settlement price difference by cash settlement. There are broad and narrow definitions of funds. In a broad sense, funds are the general names of institutional investors, including trust and investment funds, unit trust funds, provident funds, insurance funds, retirement funds and funds of various foundations. Funds in the existing securities market, including closed-end funds and open-end funds, have the characteristics of income function and value-added potential. From the perspective of accounting, fund is a narrow concept, which means funds with specific purposes and uses. Because the investors of the government and institutions do not require investment returns and investment recovery, but require the funds to be used for designated purposes according to the law or the wishes of the investors, funds are formed. Payment voucher expressed in foreign currency for international settlement. The International Monetary Fund's interpretation of foreign exchange is that foreign exchange is a creditor's right held by the monetary administrative authorities (central bank, monetary institutions, foreign exchange stabilization fund and the Ministry of Finance) in the form of bank deposits, treasury bonds of the Ministry of Finance, long-term and short-term government securities, etc., which can be used when the balance of payments is in deficit. Pressure-sensitive paper bills are documents made according to a certain form, which indicate the obligation to pay a certain amount of money, and are vouchers for cashiers or delivery of goods. In a broad sense, bills refer to all kinds of securities, such as bonds, stocks, bills of lading and so on. In a narrow sense, negotiable instruments only refer to the negotiable securities for the purpose of paying money, that is, the negotiable securities issued by the drawer according to the negotiable instruments law, which are unconditionally paid by himself or unconditionally paid by others to the payee or holder. In China, bills are bills of exchange, checks and promissory notes. Bill generally refers to negotiable securities that are issued by the drawer in business, unconditionally agreeing to pay a certain amount by themselves or asking others. The holder has certain rights to buy and sell futures now, but the subject matter will be settled or delivered in the future. This subject matter can be a commodity such as gold, crude oil, agricultural products, financial instruments and financial indicators. The delivery date of futures can be one week later, one month later, three months later or even one year later. A contract or agreement to buy or sell futures is called a futures contract. The place where futures are bought and sold is called the futures market. Investors can invest or speculate in futures. Improper speculation on futures, such as short selling out of stock, can lead to turbulence in financial markets. Bills include: bills of exchange, promissory notes, checks, bills of lading, certificates of deposit, stocks, bonds and so on. Trust is a special property management system and legal act, and it is also a financial system. Trust, banks, insurance and securities together constitute a modern financial system.