Definition 1 (By Myers-2)

Testing is the process of executing a program with the intent of finding errors.

Definition 2 (By Myers-2)

A successful test is one that uncovers an as-yet-undiscovered error.

Definition 3 (By W. Dijkstra-125)

Testing can show the presence of bugs but never their absence.

Definition 4 ( By E Miller-84)

Program testing is a rapidly maturing area within software engineering that is receiving increasing notice both by computer science theoreticians and practitioners. Its general aim is to affirm the quality of software systems by systematically exercising the software in carefully controlled circumstances.

Definition 5 (By James Bach-83)

Testing is a support function that helps developers look good by finding their mistakes before anyone else does.

Definition 6 (By Cem Kaner-85)

Software testing is an empirical investigation conducted to provide stakeholders with information about the quality of the product or service under test, with respect to the context in which it is intended to operate.

Definition 7 (By Miller-126)

The underlying motivation of program testing is to affirm software quality with methods that can be economically and effectively applied to both large-scale and small-scale systems.

Definition 8 (By Craig-117)

Testing is a concurrent lifecycle process of engineering, using and maintaining testware (i.e., testing artifacts) in order to measure and improve the quality of the software being tested.