bottom up approach vs top down
Testing takes place from top to bottom.
High-level modules are tested first and
then low-level modules and finally
integrating the low-level modules to
a high level to ensure the system is
working as intended. Stubs are used as
a temporary module if a module is
not ready for integration testing.
It is opposite of the Top-Down Approach.
Testing takes place from bottom to up.
Lowest level modules are tested first
and then high-level modules and finally
integrating the high-level modules to a
low level to ensure the system is
working as intended. Drivers are used
as a temporary module for integration testing.