For many years, when it came to email, the only solution was something known as PGP, which was quite complicated and only accessible to the tech-savvy.
这么多年来，对电邮来说， 唯一的方法就是PGP（良好隐私密码法） 但这个方法非常复杂， 只有精通技术的人才懂得如何使用。