Dollar bonds refer to bonds denominated in dollars issued outside the United States. Bonds are creditor's rights and debt certificates issued to investors when the government, financial institutions and industrial and commercial enterprises directly borrow money from the society to raise funds, and promise to pay interest at a certain interest rate and repay the principal according to the agreed conditions. The essence of bonds is the proof of debts. There is a creditor-debtor relationship between bond buyers and issuers. The issuer is the debtor and the investor (bondholder) is the creditor. Bond is a valuable security. Because the interest of bonds is usually determined in advance, bonds are a kind of fixed-interest securities.