The module design phase can also be referred to as low-level design. The designed system is broken up into smaller units or modules and each of them is explained so that the programmer can start coding directly. The low level design document or program specifications will contain a detailed functional logic of the module, in pseudocode:

► database tables, with all elements, including their type and size

► all interface details with complete API references

► all dependency issues

► error message listings

► complete input and outputs for a module.

The unit test design is developed in this stage.