I just give my means of testing:
testing means you just play as different roles:
first as a customer:what a customer need,what I need test
second as a designer:what the customer need,what the designer should designed,what I test
third,as a programmer:
what the designer designed,what the programmer should programme,what the I should test
fourth, as a thinker:
this is an important role, no thought,you are just a machine;no thought,means no good test.
Testing is a tool to reduce the defects in the created application at the production stage before the application is released for final adaptation.These defects detected sooner the better as it results in decreasing the application cost to the user.
My two cents:
Testing means understanding the application under test completely. You have a thorough understanding of all functionality, inputs, outputs, and platforms on which it will run.
Testing means you understand the SDLC, the current test methodology being practiced at your location, the various methods and tools at your disposal which can assist you in your job.
Testing means you are continuously learning and improving your techniques through any means possible.
Testing means you can take the application and simulate the user by entering both correct and incorrect data and you know what the output in both cases will be.
Testing means you own the application and you will attempt to locate every defect within it.
Testing means you, and only you are responsible for the end product of your company and therefore you have an obligation to insure a quality product is delivered, with as few minor defects as possible in the time allotted to you for validation of the application.
Success is the ability to go from one failure to another with no loss of enthusiasm.
~ Winston Churchill ~