In this chapter, we took a brief look at how APIs work in general, the RESTful API approach to semantic URL paths and arguments, and created a bare bones API. We used Postman REST Client to interact with the API by consuming endpoints and testing the different types of request methods (GET, POST, PUT, and so on). You also learned how to consume an external API endpoint by using the third-party node module Request.

In the next chapter, we will revisit our original application as we implement best practices by introducing testing in Node.js. We'll take a look at popular testing frameworks and write tests for the application to prove that our code works as expected.