Software testing engineers check programs for their functionality. A testing engineer's job includes designing, building and implementing effective testing strategies. Testing engineers utilize three types of testing strategies which are known as black box, white box and gray box testing. As a software tester, you'll be involved in the quality assurance stage of software development and deployment. You'll conduct automated and manual tests to ensure the software created by developers is fit for purpose and any bugs or issues are removed within a product before it gets deployed to everyday users.