Matrix variables and path variables are a great way to bind variables in the URL request path. However, there is one more way to bind variables in the HTTP request, not only as a part of the URL but also in the body of the HTTP web request; these are the so-called HTTP parameters. You might have heard about GET or POST parameters; GET parameters have been used for years as a standard way to bind variables in URLs, and POST is used to bind variables in the body of an HTTP request. You will learn about POST parameters in the next chapter during form submission.
Okay, now let's see how to read GET request parameters in the Spring MVC style. To demonstrate the usage of a request parameter, let's add a product details page to our application.