In order to get started, let's pull up the docs page so you know where it lives if you ever want to look at any other features that it has to offer. If you Google supertest, it should be the first result:

It's the VisionMedia repository and the repository itself is called SuperTest. Let's switch over to the repository page and we can take a quick look at what it has to offer. On this page, we can find installation instructions and introduction stuff. We don't really need that. Let's take a quick look at an example:

As shown in the previous screenshot, we can see an example of how SuperTest works. We create an Express application, just like we normally would, and we define a route. Then we make a call to the request method, which is provided by SuperTest, passing in our Express application. We say we want to make a get request to the / URL. Then we start making assertions. There's no need to manually check either the headers, the status code, or the body. It has built-in assertions for all of that.