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Insomnia allows you to send requests without having to open a browser. The browser shows you the result of many requests with pictures, CSS styles, and fancy buttons. The most popular tool to deal with API requests is Postman. I personally prefer Insomnia, cause it’s much easier and basically does the same thing. It’s handy when it comes to exploratory testing, or when you want to share the requests with developers. In Insomnia the organized collection of the requests is called Workspace.