It stands for Ghost in the Shell Stand Alone Complex, the series based on the universe created by Masamune Shirow back in 1989 ( if I pulled from wikipedia and ).
I must confess that to me with tender shocked when 16 or 17 years saw the movie adaptation that was Ghost In The Shell. I was beginning to study philosophy, the third part really piqued my curiosity during my school years and the only thing that really got to go beyond being a hobby ... but that's another story.
That movie struck me as a work of art as idea appealed to me and touched me as geek and fan. Today I saw the last episode of GITS SAC series and almost ashamed to say, but I cried and everything ... and I believe that the most accurate thing I can say is that fucking piece of art, thanks! Even with the high expectations I had was better.
See it if you can, live it if you succeed in following it.
Now only I have yet to see a ova: _ (and then I spent all that exists today in this series.