What is Mocking?

Mocking, in the context of software testing, is a technique used to isolate the unit under test by replacing its dependencies with controlled substitutes, called 'mocks'. This allows developers to verify the behavior of the unit in isolation, without relying on external systems or components that may be unavailable, unreliable, or slow. Mocks are typically programmed to simulate specific responses to method calls, enabling testers to assert that the unit interacts with its dependencies as expected.