What is Intelligent Design?

The Intelligent Design Movement is authored by William Dembski. It provides some historic background about Intelligent Design and contains this paragraph:

What then is Intelligent Design? Intelligent Design begins with the observation that intelligent causes can do things which undirected natural causes cannot. Undirected natural causes can place scrabble pieces on a board, but cannot arrange the pieces as meaningful words or sentences. To obtain a meaningful arrangement requires an intelligent cause. This intuition, that there is a fundamental distinction between undirected natural causes on the one hand and intelligent causes on the other, has underlain the design arguments of past centuries.

A meaningful arrangement of parts characterizes objects of known design. Writing is an example. The purposeful arrangement of symbols being characteristic of design. There is also this:

To say intelligent causes are empirically detectable is to say there exist well-defined methods that, on the basis of observational features of the world, are capable of reliably distinguishing intelligent causes from undirected natural causes. Many special sciences have already developed such methods for drawing this distinction-notably forensic science, cryptography, archeology, and the search for extraterrestrial intelligence (as in the movie Contact).

Whenever these methods detect intelligent causation, the underlying entity they uncover is information. Intelligent Design properly formulated is a theory of information. Within such a theory, information becomes a reliable indicator of intelligent causation as well as a proper object for scientific investigation. Intelligent Design thereby becomes a theory for detecting and measuring information, explaining its origin, and tracing its flow. Intelligent Design is therefore not the study of intelligent causes per se, but of informational pathways induced by intelligent causes.

The generation of information stored and conveyed within symbolic systems is an indicator of design. Alphanumeric symbols have their counterpart in the realm of biology- codons composed of nucleotide "letters."