Part I. Introduction to Automata Theory
An automation is defined as a system that performs certain functions without human intervention. It accepts some input as row materials and converts it to a product under the guidance of control signals. An automation can be designed to perform a variety of tasks related to various domain of human life. In terms of computer science, an automation is an abstract model of a digital computer. An automation has some
following figure shows the representation of an automation.
An automation has a mechanism for reading input. It is assumed that input is in a file. The input file is divided into cells. Each cell can hold one symbol. Input mechanism can read input file from left to right.
The automation can produce output of some form.
An automation can have a temporary storage device. the storage device can consist of unlimited number of cells. The automation can read and change the contents of the storage cells.
Automation has a control unit. At a given time, control unit is in some internal state.
2 Automata Theory
automata theory is the study of abstract computing devices or machines.
The study of automata is important because ,
1. Automata theory plays an important role when we make software for designing and checking the behaviour of a digital circuit.
2. The lexical analysis of a compiler breaks a program into logical units, such as variables, keywords and punctuation using this mechanism.
3. Automata theory works behind software for scanning large bodies of text, such as web pages to find occurrence of words, phrases etc..
4. Automata theory is a key to software for verifying systems of all types (software testing).
5. Automata theory is the most useful concept of software for natural language processing.
Definition of an Automation
an automation is defined as a program where energy, material and information are transformed, transmitted and used for
performing some functions without direct human intervention.
Example: Automatic machine tools,
Automatic packing machines,
Automatic photo copying machines.
Different classes of automata are ,
Finite automata, and
We will learn both of them in detail.