WatiN (Web Application Testing In .Net) is a free open source automation library for testing web applications. It provides an API for interacting with web browsers such as Internet Explorer and Chrome. It allows developers to write test scripts in .NET languages such as C# and VB.NET. WatiN enables developers to write robust, maintainable automated tests for web applications. It simplifies the process of creating and manipulating web elements, and provides a robust API for programmatically navigating web pages. WatiN also offers support for HTML5 and AJAX-driven web applications, making it a powerful and versatile tool for web application testing.
Discontinued The project seems to be no longer developed. The latest version, 5.0.0, released in October 2013, can still be downloaded from Github.