This document discusses real unit testing and the use of mock frameworks. It provides an introduction to unit testing and why it is important. It explains that real unit testing involves mocking dependencies so that units can be tested in isolation without concerning dependencies. The document then discusses mock objects and frameworks like Mockito that allow creating mock dependencies. It provides examples of how to use Mockito to mock dependencies and test units without their implementation. It also covers some Mockito features and limitations as well as best practices for unit testing.