密码学是一门古老而深奥的学科，它对一般人来说是莫生的，因为长期以来，它只在很少的范围内，如军事、外交、情报等部门使用。计算机密码学是研究计算机信息加密、解密及其变换的科学，是数学和计算机的交义学科，也是一门新兴的学科。随着计算机网络和计算机通讯技术的发展，计算机密码学得到前所未有的重视并迅速普及和发展起来。在国外，它已成为计算机安全主要的研究方向，也是计算机安全课程教学中的主要内容。

-Cryptography is an ancient and esoteric disciplines, it is ordinary people born Mo, since a long time, only in a few within, such as military, diplomatic, and intelligence departments. Computer cryptography is to study the computer information encryption, decryption and transformation of science, mathematics and computers, cross-discipline, but also a new subject. As computer networks and computer communications technology, computer cryptography has received unprecedented attention and the rapid spread and develop. In other countries, it has become a major research direction of computer security, but also teaching computer security in the main content.