Testing is the process of evaluating a system and its components with to find that whether it satisfies the specified requirements or not.
Testing is executing a system in order to identify any errors , missing requirements or gaps in contrary to the actual requirements.
Software testing is a process of making access to the functionally of a software program.
Software testing is performed to verify that the completed software product functions according to the requirements defined by Clint.
Software testing is the process of evaluation a software item to identify differences between given input and expected output. Testing is a process that should be done during the development process of software. In other words software testing is a validation and verification process.