Software testing is a procedure to check the software code for correctness, i.e. to check whether the results produced by the software are the same as the expected results that the software must produce.

软件测试是检查软件代码正确性的过程，即检查软件产生的结果是否与软件必须产生的预期结果相同。

Testing is a process that is performed with every phase of the software development from the very initial stage itself. It is a myth that software testing takes place only after the whole software is completed. If this is still the case anywhere, then this practice must be strictly avoided to make the software efficient both in terms of quality and cost because as soon as the error in the software gets detected, the easier it is to correct and resolve it.

从软件开发的最初阶段开始， 测试就是在软件开发的每个阶段执行的过程。 神话是仅在整个软件完成后才进行软件测试。 如果仍然存在这种情况，那么就必须严格避免这种做法，以使软件在质量和成本上都高效，因为一旦发现软件中的错误，就更容易纠正和解决它。

As the testing of the code takes place from the ideation phase itself, there are different levels defined for it. These levels are as follows,

由于代码测试是从构想阶段本身进行的，因此为它定义了不同的级别。 这些级别如下：

1. Unit testing

   单元测试

2. Integration testing

   整合测试

3. System testing

   系统测试

4. Acceptance testing

   验收测试

1)单元测试 (1) Unit testing)

A unit of software is its modules. Therefore, unit testing is performed while building the modules of the software. This is done by the developer itself or sometimes by a group of developers. As the module is much small and precise for its functionalities, it is much easier to observe it for the performance and error are also easy to detect and recover in this phase. This turns to be a very crucial step while developing a cost-effective good quality software because the more optimized the modules will be after this level, the fewer problems would occur in the later testing levels.

软件的一个单元就是它的模块。 因此，在构建软件模块时执行单元测试。 这是由开发人员本身或有时由一组开发人员完成的。 由于该模块的功能非常小巧且精确，因此在此阶段更容易观察它的性能，并且错误也很容易检测和恢复。 在开发具有成本效益的高质量软件时，这是非常关键的一步，因为在此级别之后模块越优化，在以后的测试级别中出现的问题就越少。

2)整合测试 (2) Integration testing)

It is the second level of testing that is performed while integrating different modules. A group of modules, also called subprograms are integrated and their behavior is checked whether they are performing the same as expected after integration also. Here, it is not mandatory to integrate all the modules of the entire software and then do the testing, but some modules can also be checked and this process can incrementally take place until the whole software is built and integrated.

这是集成不同模块时执行的第二级测试。 集成了一组模块，也称为子程序，并在集成后检查它们的行为是否与预期的一样。 在此，并不一定要先集成整个软件的所有模块，然后再进行测试，但是也可以检查某些模块，并且可以逐步进行此过程，直到构建和集成整个软件为止。

3)系统测试 (3) System testing)

This level of testing is performed after the whole software is completed and all its module is integrated. The software is then compiled and run on the machine and the testing to check the following is performed on it,

在完成整个软件并集成所有模块之后，才执行此级别的测试。 然后编译该软件并在计算机上运行，​​并在其上进行测试以检查以下各项，

1. Functionalities that the software must offer

   该软件必须提供的功能

2. Performance in different cases

   在不同情况下的表现

3. Security

   安全

4. Portability

   可移植性

4)验收测试 (4) Acceptance testing)

This is the final level of testing which is performed just before the software is ready to hand over to the customer. In this testing level, the software is tested for all the user interactions with the software and the responses produced by the software.

这是在软件准备好移交给客户之前执行的最终测试级别。 在此测试级别中，将测试该软件的所有用户与该软件的交互以及该软件产生的响应。

The acceptance testing further involves three levels,

验收测试还涉及三个级别，

1. Alpha testing

   阿尔法测试

2. Beta testing

   Beta测试

3. Gamma testing

   伽玛测试

翻译自: