Quantum software testing is an emerging software engineering field that focuses on testing quantum programs to find quantum faults in the programs cost-effectively. Given the foundations in quantum mechanics, the way quantum programs perform computations is significantly different than the classical programs. Therefore, quantum software testing also differs than classical software testing. There has been quite an interest in building quantum software testing techniques since 2019 in the software engineering community. Thus, we aim to provide an introduction to quantum software testing to the community. In particular, we will present the basic foundations of quantum computing and quantum programming as circuits, followed by the current state of the art on quantum software testing. Next, we will present some basic quantum software testing techniques and finally give the research directions that deserve attention from the software engineering community.