[wellylug] 'shared state'

[Bret Comstock Waldow]

As a process continues, it acts on something (generally).  The state of
what it acts on is it's 'state'.  When you do your taxes, the state
proceeds from rules without data, to partially filled in data &
calculations, to complete data & calculations.  At any point, what you
have is the current state of the process.

If two processes both work on the same data, then they 'share state' -
at least for the part they share.  The (overall) process is cooperative.

If each process proceeds to it's (correct) conclusion without reference
to any other, then there is no 'shared state'.  It's much simpler, as
there's no waiting, synchronising of intermediate results, and so forth.

Cheers,
Bret