According to a time-honored tradition in finance, it says that it's a promise to pay $1, but it's not worth $1 today.

由于资金有时间价值,他说他承诺支付一美元,但在此时此刻它并不值一美元

耶鲁公开课 - 金融市场课程节选

The goldsmith in your town writes out a note saying, I will pay to the bearer of this note so much gold, and then the bearer could be anyone.

你居住城镇的金匠写下票据并承诺,我会付给持票人这么多数量的金子,任何人都可以是持票人

耶鲁公开课 - 金融市场课程节选