In this chapter, we discussed the HTTP request, the principles of the REST API, and the authentication and authorization mechanism. We outlined the operation of our web API and defined that an operation is a combination of a URI and an HTTP request. Then, we created a working REST API to perform CRUD operations on our users. 

We created endpoints for performing CRUD operations on medical practitioners as well. It should be noted that the endpoints and code implemented in this book should be used as a reference point. There are several possibilities, patterns, and architectures in which the same functionalities can be achieved. We encourage users to practice more. As the saying goes, practice makes perfect.