How do you develop a test plan and schedule? Describe bottom-up and top-down approaches.

A test plan is contract among the testers and the project team explaining the role of testing in the project. The purpose of test plan is to prescribe the scope, approach, resources and schedule of the testing activities. To recognize items being tested, the feature to be tested, the testing task to be performed, the personnel responsible for every task and the risks associated with the plan. From this, it is imperative that test plan is made by taking inputs from the product development team, keeping in consideration the project deadlines and risks included while testing the product or components of the product