Durability : The extent to which the program anticipates problems due to errors (not bugs). This includes situations such as incorrect, inappropriate or corrupt data, unavailability of needed resources such as memory, operating system services, network connections, user error, and unexpected power outages.

Validity : the work environment of the program: the ease with which the program can be used for its intended purpose or even in some cases for unexpected purposes. This includes a wide range of textual, graphic, and sometimes hardware elements that improve the clarity of the coherence intuition and the completeness of the software user interface.

Portability: The set of underlying computer hardware and operating systems that can compile / interpret and run a program's source code. This depends on differences in the programming facilities offered by different platforms including hardware and operating system resources, expected behavior of the device and operating system, and the availability of platform-specific compilers (and sometimes libraries) for the source code language.

Maintainability: The ease with which software can be modified by its current or future developers in order to make improvements, customizations, fix bugs and security holes, or adapt it to new environments. Good practices [7] during initial development make a difference in this regard. This quality may not be directly apparent to the end user but it may significantly affect the software's long-term fate.

Efficiency / Performance : measure the system resources a program consumes (processor time, memory space, slow devices such as disks, network bandwidth and even user interaction to some extent): the less the better. This also includes careful resource management eg cleaning temporary files and eliminating memory leaks .