Every time a test runs, the result is saved along with it's assertions and whether they passed or failed. Test results are one of the more useful parts of a test; exploring specific failures and calculating long-term regressions, for example.
Test results can be accessed from the "Results" tab of the correspond test's web service page:
The most interesting part of a test result is knowing if the assertions passed or failed. This information is laid out on the 'Assertions' view of each test result.
Each assertion that was defined will show, with a detailed description of the reason for the pass or failure -- as seen in the screenshot above.
The request body is on the 'Request' tab of the test result page. This contains all the information that was sent in the HTTP request with the test; including headers and request body.
You can configure a lot of things about the request, add custom headers, and set up other environment you need. See the test configuration page for more information.
The response body contains all the information sent back from the HTTP request during your test (for example, a website 'responds' with an HTML page). You can see all of the headers, the body, response time, and other things.
Most of the time, you'll be making assertion on something related to the response. For more info on setting up and configuration assertions, see here.
The Setups tab contains all of the information about any Setup steps that were run during the test. The captured variables, request body, and response body are all available so you can debug and validate that your setup steps are working correctly.
For more info on adding Setup Steps, see this section.