随着计算机技术的迅速发展和越来越广泛深入地应用于国民经济和社会生活的各个方面，随着 软件系统的规模和复杂性与日俱增，软件的生产成本和软件中存在的缺陷和故障造成的各类损失也 大大增加，甚至会带来灾难性的后果。软件质量问题已成为所有使用软件和开发软件的人关注的焦 点。由于软件是人脑的高度智力化的体现和产品这一特殊性，不同于其他科技和生产领域，因此软件与生俱来就有可能存在着缺陷。-With the rapid development of computer technology and the more extensively used in the national economy and social life in all its aspects, with the growing size and complexity of software systems, software production costs and software defects and faults caused various types of losses also increased significantly, even catastrophic consequences. Software quality has become the focus of all those who use the software and software development concern. Because the software is highly intellectual expression and product of the special nature of the human brain, unlike other areas of technology and production, so the software may be born with a defect exists.