Oreo is a free Chrome add-on developed by Todd. It is designed to help developers quickly flush the Chrome DNS resolver cache and close all opened sockets. This tool is particularly useful for developers who need to test their applications in a clean environment.

To use Oreo, users must first enable a feature in Chrome by navigating to `chrome://flags/#extensions-on-chrome-urls`. Once the feature is enabled, Oreo can be accessed and utilized. With Oreo, developers can easily flush the DNS resolver cache and reload their pages, ensuring that they are testing their applications in a fresh and accurate environment.

Oreo is a handy tool for developers looking to streamline their testing process. By providing a simple and efficient way to flush the Chrome DNS resolver cache, Oreo helps developers ensure the accuracy of their tests and avoid any potential issues caused by cached data.

Please note that Oreo is only available for the Chrome platform and falls under the category of Browsers, specifically in the Add-ons & Tools subcategory. It is a free tool, making it accessible to developers of all levels.