The algorithm and program.
The absence of a formal definition of the algorithm led to a number of misconceptions. Thus, the German mathematician Gottfried Wilhelm Leibniz (1646-1716) tried to build nothing less than a general algorithm for solving an algebraic problem. Similar attempts in a more concrete form taken even at the beginning of this century. The failure of these searches is gradually led to the conclusion that such problems are algorithmically unsolvable. The problem of the formal definition of the algorithm is even more acute. Her solution was found only in the 30s of this century. It was based on the realization that any algorithm does not operate with real objects and their symbolic maps. Somewhat later, this idea was expressed more precisely: the objects of algorithms are the information in digital form. It also emerged that a guarantee of accuracy and uniqueness of the algorithm is unambiguous and precise language, in which he described. The reason for ambiguity in the intuitive definition of the algorithm is that it implicitly assumed to be the executor person receiving instructions in natural language, one of the most important features of which - multiple. It is due to the presence of homonyms, synonyms, context, city e. significant dependence of the meaning of the preceding statement, etc. Human language is peculiar redundancy: understanding of the text is often not precluding a reservation slips, omission of letters or whole words and abbreviations. All these features contribute to the imagery, the brightness and saturation in the expression of a variety of thoughts, emotions, but the difficult process of formalization of many concepts, including the algorithm.
Alphabet of information words, which operates the Turing machine, can be arbitrary, but finite, it is called external. In addition it is necessary to refer to the internal alphabet of internal states, and some special situations. As a result of work of the Turing machine allows a symbolic description in the form of a special jump table. Each row in this table to the current input symbol and current state is associated with an output symbol, new state and an indication of left or right of the current need to take the next character processed. Table rows are called commands and the table as a whole - program. MT work begins with the "settings" at the initial internal state and the first symbol "input word. On them in the program is given command, and as a result - an output symbol, new state and the place from which to consider the next input character. This happens until a special "final" state, corresponding to the solution of the problem.
Software management in Central Asia.
So, we can assume the CA device that implements a specific algorithm of processing information. Its main activities - operations on the symbols - performed combinational circuits. But it does occur and other processes such as change of state schemes with memory, write the words in memory. They should all be "tied" to certain ticks, finally, there should be fixing device clock moments themselves.
This rather complex role in the model of Turing charged a man and a real CA - control device. As a result of any CA can be composed of random access memory (memory), an operating unit (OU) and the control unit (CU).