I operated a few small changes to the intro, finished section "A Brief History of Data Sharing" and worked into the discussion of shared and non-shared globals.

See http://erdani.com/d/fragment.preview.pdf

I still have in mind that the flagship approach is message passing, but in order to explain the "no-share" approach I also need to explain under what conditions sharing is actually possible.

Feedback is welcome. Thanks!


Andrei