| Use Case: It is prepared by Business analyst in the Functional Requirement Specification (FRS), which is nothing but steps which are given by the customer.
Test cases: It is prepared by test engineer based on the use cases from FRS to check the functionality of an application thoroughly.
Test Plan: Team lead prepares test plan, in it he represents the scope of the test, what to test and what not to test, scheduling, what to test using automation etc. | | |