from
The Free On-line Dictionary of Computing (8 July 2008)
portability
portable
<operating system, programming> The ease with which a piece of
software (or {file format}) can be "ported", i.e. made to run
on a new {platform} and/or compile with a new {compiler}.
The most important factor is the language in which the
software is written and the most portable language is almost
certainly {C} (though see {Vaxocentrism} for counterexamples).
This is true in the sense that C compilers are available for
most systems and are often the first compiler provided for a
new system. This has led several compiler writers to compile
other languages to C code in order to benefit from its
portability (as well as the quality of compilers available for
it).
The least portable type of language is obviously {assembly
code} since it is specific to one particular (family of)
{processor}(s). It may be possible to translate mechanically
from one assembly code (or even {machine code}) into another
but this is not really portability. At the other end of the
scale would come {interpreted} or {semi-compiled} languages
such as {LISP} or {Java} which rely on the availability of a
portable {interpreter} or {virtual machine} written in a lower
level language (often C for the reasons outlined above).
The act or result of porting a program is called a "port".
E.g. "I've nearly finished the {Pentium} port of my big bang
simulation."
Portability is also an attribute of {file formats} and depends
on their adherence to {standards} (e.g. {ISO 8859}) or the
availability of the relevant "viewing" software for different
{platforms} (e.g. {PDF}).
(1997-06-18)