UbuntuLinux

http://en.wikipedia.org/wiki/Porting

In computer science, porting is the process of adapting software so that an executable program can be created for a computing environment that is different from the one for which it was originally designed (e.g. different CPU, operating system, or third party library).
The term is also used in a general way to refer to the changing of
software/hardware to make them usable in different environments.

Software is portable
when the cost of porting it to a new platform is less than the cost of
writing it from scratch. The lower the cost of porting software,
relative to its implementation cost, the more portable it is said to be.