I have used the GitHub API to show the basic HTTP methods. You can sign up to GitHub and get an authentication token if you wish to explore the API. In the next chapter, we will create our own API. In these examples, we act as a consumer of an API. In these examples, I am using Fiddler to make the request. You can use any tool you like; other commonly used tools are Postman, which is built into the Chrome browser or Advanced Rest Client. Idempotent is a term used for REST APIs; simply put, when you call a method, it will return the same data no matter how many times you call it. In the following examples, I will list which methods are idempotent.