This article is from the Jobs FAQ, by Snoopy snoopy-at-sopwith.uucp.
Abbreviations can be useful in the Subject line, but there is
far less need for them in the body of your article.
If you use abbreviations, make sure that they are commonly
used ones. Do not make up your own.
To quote from an article by Igor Chudov:
f u cn rd ths, u cn gt a gd jb n cmptr prgrmmng.
Do not shorten terms so much that information is lost. For
example, there are many computer programs with "DOS" in their
name. If you mean MS-DOS, say "MS-DOS", not "DOS". If you
are referring to a particular computer display windowing
system, tell the reader which one. Say "X-Windows" or
"MS-Windows", or whatever, not just "windows". The term "PC"
can mean "generic personal computer, including IBM-PCs,
MacIntoshes, Ataris, etc.", it can mean "Intel based personal
computer hardware platform running any of a wide variety of
software", or it can mean "Intel based personal computer
running MS-DOS". In electronics it may mean "printed circuit".
In non-computer contexts it may mean "politically correct".
If you use the term "PC" be sure it is clear what you mean.