Selenium也是一个用于Web应用程序测试的工具。Selenium 测试直接运行在浏览器中，就像真正的用户在操作一样。支持的浏览器包括IE,">Mozilla和Firefox等。这个工具的主要功能包括：测试与浏览器的兼容性--测试你的应用程序看是否能够很好得工作在不同浏览器和操作系统之上。测试系统功能--创建衰退测试检验软件功能和用户需求。 支持自动录制动作，和自动生成.Net、Java、Perl等不同语言的测试脚本。
Selenium 是 ThoughtWorks 专门为 Web 应用程序编写的一个验收测试工具。据 Selenium 主页所说，与其他测试工具相比，使用 Selenium 的最大好处是：
Selenium 测试直接在浏览器中运行，就像真实用户所做的一样。Selenium 测试可以在 Windows、Linux 和 MacintoshAnd 上的 Internet Explorer、Mozilla 和 Firefox 中运行。其他测试工具都不能覆盖如此多的平台。使用 Selenium 和在浏览器中运行测试还有很多其他好处。
下面是主要的两大好处：
通过编写模仿用户操作的 Selenium 测试脚本，可以从终端用户的角度来测试应用程序。通过在不同浏览器中运行测试，更容易发现浏览器的不兼容性。Selenium 的核心，也称 browser bot，是用 JavaScript 编写的。这使得测试脚本可以在受支持的浏览器中运行。browser bot 负责执行从测试脚本接收到的命令，测试脚本要么是用 HTML 的表布局编写的，要么是使用一种受支持的编程语言编写的。
Selenium v2.0b3发布原文如下：
It’s been about 5 weeks since the release of beta 2, so we’re very pleased to announce that Selenium 2.0b3 has just been released simultaneously for Java, .Net, Ruby and Python. You can download it from Selenium HQ or from the Google Code site. This release focused on providing excellent support for the next generation of browsers, particularly IE 9 and Firefox 4, and we think you’ll like what you’ll find.
·Restructured documentation at Selenium HQ
·An improved user interaction API
Including experimental IME support on Windows.
·Alerts and prompts handling for IE.
·Marked the following APIs as obsolete in .Net:
IRenderedWebElement.Hover()
IOptions.Speed
·Even more improvements to the Java webdriver-backed selenium
We’ll document the migration path before 2.0b4 is out!
·A significantly faster Android Driver
As well as these changes, there’s also the regular clutch of bug fixes and tweaks. For the number crunchers, there were a total of 331 changes that landed in the 5 weeks since the last release, with the 5 most active contributors working on each of the different languages supported by Selenium.
In addition to the enormous thanks that go to the developers, I’d like to add a big thank you to the Mozilla engineers who chipped in on the IRC channel at the last minute to help us work through some issues with Core. We’d not have been able to get this release out when we did without their help. Thank you Mozilla!
The next release will be focused on stabilization work, reducing our bug count and adding support for Grid 2.0.