DevNet Associate DEVASC 200-901 Official Certification Guide by Adrian Iliesiu (z-lib.org)

In HTTP, in order to make a successful request to the
server, the client needs to include four items:

URL (uniform resource locator)

Method

List of headers

Body

The following sections look at each of these items in
detail.

Uniform Resource Locator (URL)

An URL is similar to a house address in that it defines
the location where a service resides on the Internet. A
URL typically has four components, as shown in Figure
7-7:

Protocol

Server/host address

Resource

Parameters

Figure 7-7 Anatomy of an HTTP URL

These four components are shown in the Figure 7-7.

As you can see, the server or host address is the unique
server name, /api/rooms/livingroom defines a resource
to access, and lights?state=ON is the parameter to send
in order to take some action.