Portability

Portability is the idea that code can be easily transfered between operating systems and system architectures with little or no changes required. It is often the result of using a significant level of abstraction from the hardware.

For example, assembly code is not very portable as many different system architecture's require different code (and have different instructions), whereas higher-level languages (such as C, C++, Java, etc.) are abstract enough that the same source code can be used on many different architectures through the use of a compiler.