测试是软件开发的重要环节之一。按照软件开发的过程测试可分为：单元测试、集成测试、系统测试、域测试(Field test)等。我们这里将讨论面向程序员的单元测试。本文首先介绍单元测试的定义，为什么要使用单元测试?单元测试能给我们带来的好处。之后我们将介绍单元测试的范畴，最后将讨论很多朋友不写单元测试的借口。希望本文能够再次引起您对单元测试的重视，并说服您老板对编写单元测试的支持，能让美丽的单元测试真正应用到您的项目之中-Testing is an essential part of software development. Testing in accordance with the process of software development can be divided into: unit testing, integration testing, system testing, field testing (Field test) and so on. Here we will discuss unit test for programmers. This paper introduces the definition of unit testing, why use the unit tests? Unit test will give us the benefits. Then we will introduce the scope of unit testing, and finally will discuss the many friends an excuse not to write unit tests. I hope this will once again draw your attention to the unit tests, and convince your boss to support the preparation of unit tests, unit tests really make a beautiful project being applied to your