When exactly Driver and Stub concept comes into picture in Different levels of testing?

Of all the different phases of testing starting with Component ->Integration -> System -> Acceptance testing, the concept of Driver and Stub creeps into the picture mostly during Integration testing however at times this might also be needed during component testing to validate few features of an individual module.

We usually think of Driver and Stub if we have a developed module and few undeveloped modules. Few features of developed module have its dependency on undeveloped module/s. So, depending upon the feature of developed module with that of undeveloped module, Driver and Stub is used.