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EMC2 is modular and flexible.
 These attributes lead many to see it as a confusing jumble of little things
 and wonder why it is the way it is.
 This page attempts to answer that question before you, dear reader get
 on into the thick of things.
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EMC started at the National Institute of Standards and Technology in the
 USA.
 It grew up using Unix as it's operating system.
 Unix made it different.
 Among early Unix developers there grew a set of code writing ideas that
 some call the Unix way.
 These early EMC authors followed those ways.
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Eric S.
 Raymond, in his book The Art of Unix Programming, summarizes the Unix philosoph
y as the widely-used engineering philosophy, "Keep it Simple, Stupid" (KISS
 Principle).
 He then describes how he believes this overall philosophy is applied as
 a cultural Unix norm, although unsurprisingly it is not difficult to find
 severe violations of most of the following in actual Unix practice:
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* Rule of Modularity: Write simple parts connected by clean interfaces.
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* Rule of Clarity: Clarity is better than cleverness.
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* Rule of Composition: Design programs to be connected to other programs.
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* Rule of Separation: Separate policy from mechanism; separate interfaces
 from engines.
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Found at http://en.wikipedia.org/wiki/Unix_philosophy, 07/06/2008
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Mr Raymond offered several more rules but these four describe essential
 characteristics of the EMC2 motion control system.
 
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The 
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Modularity
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 rule is critical.
 Throughout these handbooks you will find talk of the interpreter or task
 planner or motion or HAL.
 Each of these is a module or collection of modules.
 It's modularity that allows you to connect together just the parts you
 need to run your machine.
 
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The 
\series bold 
Clarity
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 rule is essential.
 EMC2 is a work in progress -- it is not finished nor will it ever be.
 It is complete enough to run most of the machines we want it to run.
 Much of that progress is achieved because many users and code developers
 are able to look at the work of others and build on what they have done.
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The 
\series bold 
Composition
\series default 
 rule allows us to build a predictable control system from the many modules
 available by making them connectable.
 We achieve connectability by setting up standard interfaces to sets of
 modules and following those standards.
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The 
\series bold 
Separation
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 rule requires that we make distinct parts that do little things.
 By separating functions debugging is much easier and replacement modules
 can be dropped into the system and comparisons easily made.
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What does the Unix way mean for you as a user of EMC2.
 It means that you are able to make choices about how you will use the system.
 Many of these choices are a part of machine integration, but many also
 affect the way you will use your machine.
 As you read you will find many places where you will need to make comparisons.
 Eventually you will make choices, "I'll use this interface rather than
 that
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 or, 
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I'll write part offsets this way rather than that way." Throughout these
 handbooks we describe the range of abilities currently available.
 
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As you begin your journey into using EMC2 we offer two cautionary notes:
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Found at http://en.wikipedia.org/wiki/Unix_philosophy, 07/06/2008
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"UNIX was not designed to stop its users from doing stupid things, as that
 would also stop them from doing clever things." Doug Gwyn
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"Unix is user-friendly.
 It just isn't promiscuous about which users it's friendly with." Steven
 King 
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