# Functional Information

Mihai Draganescu
defines ** general information** as a *
meaningful syntactic structure*.
A. N. Kolmogorov and
G. Chaitin define the information content of a
binary string as having the magnitude order of the description used to
generate it. More precisely, Chaitin associates the amount of
information with the size of a program.

Applying the general information's definition in digital systems
** functional information** is defined as the symbolic
structure ** acting** by its formal, context dependent meaning.

Functional information develops in a three-stage process inside the digital
domain:
- in the first stage as
** informational structure**: a
* structured state* having the
meaning correlated with the functional loop of a big simple automaton
belonging to *nOS* (see Loop Based Taxonomy for Digital Systems ) with *n > 1*
- in the second stage as
** functional information**: an informational
structure(called * micro-program*)
used to
specify the actual function of a * simple & big* digital system
(belonging to *nOS* with * n > 2*)
- in the third step functional information (now embodied in
* programs*) takes the
control of the function performed computational system
(belonging to *nOS* with * n > 3*)

The * structured state* of a non-finite automaton (introduced in [Stefan '83]) is the
Cartesian product defining the state of a big and simple automaton.

Thus an information system processes data (which can be or can't be
information) through the information (the system of program-like symbolic structures)
interpreted or executed by the hardware resources of a machine.

Information has a content dependent definition, because it must be
defined according to the action controlled using it.

Functional information allows us to * segregate* the simple
(circuits) from the complex (programs) in a computing system (see also 0-State Universal Turing Machine).

Segregating simple from complex in digital system, its actual
complexity is minimized.

## References

[Stefan '83] Gh. Stefan, I. Draghici, T. Muresan, E. Barbu, * Circuite integrate
digitale* (Digitale Integrated Circuits), Ed. Didactica si pedagogica,
Bucuresti, 1983.

[Stefan '91] Gh. Stefan,: * Functie si structura in sistemele
digitale* (Function and Structure in Digital Systems), Ed. Academiei
Romane, Bucuresti, 1991.

[Stefan '97] Gh. Stefan: * Circuit Complexity, Recursion, Grammars and Information.
Multiple Morphisms*, Ed. Transilvania University of Brasov, 1997.

[Stefan work in endless progress] Gh. Stefan:
Loops & Complexity in Digital Systems. Lecture Notes on Digital Design in the Giga-Gate/Chip Era