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2015
Bangabandhu Sheikh
Mujibur Rahman
Science and
Technology University,
Gopalganj-8100 MD. Nasimul Islam
Introduction to Computers [ ] This paper is prepared and submitted to the Department of Accounting and Information Systems of Bangabandhu
Sheikh Mujibur Rahman Science and Technology University, Gopalganj-8100, Bangladesh for the requirement of
the partial fulfillment of the course Computers Fundamental (CSE-152).
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Dedicated to
My parents, thank you for your love, encouragement, and support, and for demonstrating the value of education, hard work,
and persistence and to Mr. Md. Solaiman Hossain , for giving me the helpful and prestigious support, expecting the best, and
patiently teaching me (over and over again) how to write the assignment.
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Letter of Submission
18 August, 2015
The Department of Accounting &Information Systems,
Bangabandhu Sheikh Mujibur Rahman Science & Technology University (BSMRSTU),
Gopalganj-8100.
Subject: Submission of assignment on “Introduction to Computers”.
Dear Sir,
It is my great pleasure to submit the assignment titled “Introduction to Computers” under the course “Computers
Fundamental” that is assigned us as a partial requirement of my BBA course. I am thankful to the department for allowing
me the opportunity to do the assignment on this topic. The paper has been completed by the knowledge that I have gathered
from the course “Computers Fundamental (CSE-152)”. I am thankful to all those persons who provided me important
information and gave me valuable advices.
Finally, I am truly grateful to the department for giving me this nice opportunity to work on this report, which I have
considered as a great chance for me to develop my computer concepts. Although I have tried my best, certain mistakes and
inconveniences may reside and for this I seek pardon and hope the department will accept my apologies.
Yours obediently,
Md. Nasimul Islam
Student ID: 20141112017
Session: 2014-15,
Semester-II, Year-I,
Department of Accounting & Information Systems
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Letter of Acceptance
18 August, 2015
Md. Nasimul Islam
SN: 20141112017
Semester-II, Year-I,
Department of Accounting & Information Systems,
Bangabandhu Sheikh Mujibur Rahman Science & Technology University (BSMRSTU).
Subject: Acceptance of assignment on “Introduction to Computers”.
Dear Md. Nasimul Islam,
It is my pleasure to accept your work for preparing an assignment on “Introduction to Computers”. I have gone through the
whole paper. I think the paper is highly informative & relevant. The paper is seemed original to me. I appreciate you for such
a good work.
I wish you every success in life.
With thanks
Mr. Md. Solaiman Hossain
Lecturer,
Department of Accounting &Information Systems,
Bangabandhu Sheikh Mujibur Rahman Science & Technology University (BSMRSTU).
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Acknowledgement
First of all I want to thank the immeasurable grace and profound kindness of Almighty God, the supreme authority of the
universe who bestowed me the capability of successful completion of my assignment fairly.
Computers Fundamental is really an interesting course and attending a project like this leaves us with a store of knowledge.
This type of assignment will help us in our future job. I am thankful to my course teacher Mr. Md. Solaiman Hossain, and our
academic Faculty from Bangabandhu Sheikh Mujibur Rahman Science & Technology University. He is teaching us this
interesting course so easily, that I can understand properly. It is an important course for Business students. The versatile
viewpoint and teaching style of Mr. Md. Solaiman Hossain is very nice and examples given by his throughout and lecture
are very much realistic. So it helped me to understand the topic of this course easily.
At last I would like to thank our classmates & elder brothers and sisters of AIS 1st Batch for their nice cooperation in
preparing this assignment. Many of my friends and also many well-wishers contributed ideas and made suggestions that
greatly enhanced this. I would like to thank them all.
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Executive Summery
For the fulfillment of Bachelors of Business Administration program I have to create this assignment on Introduction to
Computers under the course Computers Fundamental. First of all the basic organization topic is based with the concepts
about computer systems, its elements, importance and limitation. The types of computers consist of the basis of purpose,
signals and capacity. Finally the history and generation part will understand us the history and generation of computers.
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Table of Content
Chapter 1 Introduction 7-7
2 Basic Computer 8-8
3 Components 9-10
4 Importance and limitation 11-12
5 Types 13-14
6 History and Generation 15-17
Reference 18
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Chapter 1
Introduction 1.1 Introduction of the study
First of all the basic organization topic is based with the concepts about computer systems, its elements, importance and
limitation. The types of computers consist of the basis of purpose, signals and capacity. Finally the history and
generation part will understand us the history and generation of computers.
1.2 Objective of the study
It’s a theoretical concept about basic concept of a computer system, basic elements of computer system and importance
and limitation of computers.
1.2.1 General Objectives:
To know the basic concept of a computer system.
To know basic elements of a computer system.
To know the importance and limitation of computers.
1.2.2 Specific Objectives:
To know the basic organization.
To know the types of computers.
Collecting information about history and generation.
1.3 Methodology of the study
In here Methodology means how we will make a report? Or where from us will collect the data? There are two methodology
of making a report or assignment. There are two methods to collect data. Now I will discuss where from I collected the data.
1.3.1 Primary sources
In primary sources we can collect data from the field of an organization. it means to directly collect data from the
organization. If we make any assignment about an organization directly collect data from an organization, it will tell primary
data sources.
For example: - directly talk with a manager, visit an organization.
1.3.2 Secondary sources
In secondary sources we can collect data from the published sources of an organization. If we make an assignment about an
institution to collect data from thee published sources, it will tell the Secondary sources.
For example: - Internet, various books, newspaper (Local or international), magazine, advertisement.
After all I collected data from the secondary sources.
1.4 Limitation of the study
Every sector we face some problems and have some limitations. To make this assignment I faced huge problems such as:-
(1) Lack of available internet connection.
(2) Lack of important books.
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Chapter 2
Basic Computer
The first known use of the word "computer" was in 1613 in a book called The Yong Mans Gleanings by English writer
Richard Braithwait: "I read the truest computer of Times, and the best Arithmetician that ever breathed, and he reduceth thy
days into a short number." It referred to a person who carried out calculations, or computations. The word continued with the
same meaning until the middle of the 20th century. From the end of the 19th century the word began to take on its more
familiar meaning, a machine that carries out computations.
A computer is a general-purpose device that can be programmed to carry out a set of arithmetic or logical operation
automatically. Since a sequence of operations can be readily changed, the computer can solve more than one kind of
problem. Conventionally, a computer consists of at least one processing element, typically a central processing unit (CPU),
and some form of memory. The processing element carries out arithmetic and logic operations, and a sequencing and control
unit can change the order of operations in response to stored information. Peripheral devices allow information to be
retrieved from an external source, and the result of operations saved and retrieved.
Mechanical analog computers started appearing in the first century and were later used in the medieval era for astronomical
calculations. In World War II, mechanical analog computer was used for specialized military applications such as calculating
torpedo aiming. During this time the first electronic digital computers were developed. Originally they were the size of a
large room, consuming as much power as several hundred modern personal computers (PCs).
Modern computer based on integrated circuits are millions to billions of times more capable than the early machines, and
occupy a fraction of the space. Computers are small enough to fit into mobile devices, and mobile computers can be powered
by small batteries. Personal computer in their various forms is icons of the Information Age and is what most people consider
as “computers.” However, the embedded computers found in many devices from MP3 players to fighter aircraft and from
electronic toys to industrial robots are the most numerous.
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Chapter 3
Components
A computer is used to process data and a data processing system consists of more than just machines. Computer systems
must contain:
Hardware
Software
Humanware
Operational Procedures
3.1 Hardware
A computer system consists of two major elements: hardware and software. Computer hardware is the collection of all the
parts you can physically touch. Computer software, on the other hand, is not something you can touch. Software is a set of
instructions for a computer to perform specific operations. You need both hardware and software for a computer system to
work. Some hardware components are easy to recognize, such as the computer case, keyboard, and monitor. However, there
are many different types of hardware components. In this lesson, you will learn how to recognize the different components
and what they do.
Let's start with the computer case. This is the metal enclosure that contains many of the other hardware components. It comes
in various shapes and sizes, but a typical tower model is between 15-25 inches high. Want to know what's inside? Okay, go
get a screwdriver and let's open it up. Seriously, if you are really into computers, the best way to learn is to actually get
hands-on. To save us some time, however, have a look at this desktop computer case. A computer enthusiast replaced the
metal side panel with a transparent one, so we can have a look inside.
Although that photo looks pretty cool, it is a bit hard to recognize the individual components, especially with all the
connecting wires running through it. This figure shows a more schematic version of a desktop computer, which makes it
easier to point out the essential hardware components.
The computer case contains a power supply unit to convert general-purpose electricity to direct current for the other
components. The most critical component is the motherboard, a plastic board on which several essential components are
mounted. This includes the central processing unit, or CPU, the main memory, and expansions slots for other hardware
components. The internal hard disk drive serves as the mass storage device for data files and software applications. An
optical disk drive makes it possible to read from and write to CDs and DVDs. Other hardware components typically found
inside the computer case (but not shown in the figure) are a sound card, a video card, and a cooling mechanism, such as a fan.
A computer system also needs input devices, such as a keyboard and a mouse. To interact with a user, a computer system
also needs a display device, such as a monitor.
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3.2 Software
Computer software or simply software is any set of machine-readable instructions that directs a computer's processor to
perform specific operations. Computer software contrasts with computer hardware, which is the physical component of
computers. Computer hardware and software require each other and neither can be realistically used without the other. Using
a musical analogy, hardware is like a musical instrument and software is like a sheet music (score). Computer software
includes computer programs, libraries and their associated documentation. The word software is also sometimes used in a
more narrow sense, meaning application software only. At the lowest level, executable code consists of machine language
instructions specific to an individual processor – typically a central processing unit (CPU). A machine language consists of
groups of binary values signifying processor instructions that change the state of the computer from its preceding state. For
example, an instruction may change the value stored in a particular storage location inside the computer – an effect that is not
directly observable to the user. An instruction may also (indirectly) cause something to appear on a display of the computer
system – a state change which should be visible to the user. The processor carries out the instructions in the order they are
provided, unless it is instructed to "jump" to a different instruction, or interrupted. Software written in a machine language is
known as "machine code". However, in practice, software is usually written in high-level programming languages that are
easier and more efficient for humans to use (closer to natural language) than machine language. High-level languages are
translated, using compilation or interpretation or a combination of the two, into machine language. Software may also be
written in a low-level assembly language, essentially, a vaguely mnemonic representation of a machine language using a
natural language alphabet. Assembly language is translated into machine code using an assembler.
3.3 Humanware
Humanware refers to the persons who design, program, and operate a compute. There are numerous categories of jobs, but
the three principal positions for large computer installations are system analyst, programmer, and computer operator.
A systems analyst is a person who uses analysis and design techniques to solve business problems using information
technology. Systems analysts may serve as change agents who identify the organizational improvements needed, design
systems to implement those changes, and train and motivate others to use the systems. A programmer, computer programmer,
developer, coder, or software engineer is a person who writes computer software. The term computer programmer can refer
to a specialist in one area of computer programming or to a generalist who writes code for many kinds of software.
A role in IT, computer operators oversee the running of computer systems, ensuring that the machines and computers are
running properly. The former role of a computer operator was to work with mainframe computers which required a great deal
of management day-to-day, however nowadays they often work with a variety of different systems and applications. The
computer operator normally works in a server room or a data center, but can also work remotely so that they can operate
systems across multiple sites. Most of their duties are taught on the job, as their job description will vary according to the
systems and set-up they help manage.
3.4 Operational Procedures
Operations of data processing center require an extensive and clearly defined set of procedures for performing the essential
functions. These function generally include obtaining, preparing and entering data into the computer, processing jobs,
initiating new programs and changing or deleting old ones etc. Such procedures require actions to be taken in the event of
hardware of software malfunction.
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Chapter 4
Importance
and
limitations
4.1 Importance
Computers are used today to store, retrieve, process, and transmit data and information of all types. Though the computer is
essentially a device to store retrieve and process data, many other devices such as printers, music systems, video systems,
games, communication devices, automatic data capture devices, and control devise are now used in combination with
computers, that use the basic data input, output and processing capabilities of computer to produce highly innovative and
systems with application in practically every aspects of human activities today.
The major advantage of using computers in this way is given below.
Computers makes it possible to receive, supply and process large volumes of data at very high speed.
Computer reduces the cost of all data related operations including, input, output, storage, processing, and
transmission.
Computer greatly improves the speed of data input, output, processing, and transmission.
Computer ensures consistent and error free processing of data. However it should be noted the error free processing
is subject to correct feeding of data and correct programming.
Digitization of all kinds of information including sounds and images, combined with massive information
processing capabilities of the computer has resulted in development of application to produce physical products of
very high quality at great speed and very economically. We are all aware of the improvement in audio and video
systems including computer games using modern computer technology. However computers are also playing a big
role in manufacturing of many other physical products. For example, a computerized insta-paint system scans the
color of any surface and produces a paint of exactly matching color and shade.
The data input, output, and processing speed of computers has enabled development of many applications requiring
speedy continuous monitoring of a process or situation and responding to it very quickly in real time. For example,
a small microcomputer in a car may continuously monitor the speed. Load and other condition of the car and
accordingly control the fuel and air mixture to maximize the fuel efficiency. In an entirely different kind of
application, a computer may control the movement of a missile launched to intercept a missile fired by the enemy.
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4.2 Limitation
Computer is highly dependent on the quality of input data fed to it. Though computers are very fast in tasks that are
pre-programmed, it lake the ability of human brain to detect and correct errors that it is not specifically
programmed to do.
The task of programming a computer for a computer application is very costly and time consuming. This reduces
the utility of computers for applications that are non-repetitive.
Computer systems are rather rigid. Once a computers system is designed and programmed, making even minor
corrections or improvements can be quite costly and time consuming. For this reason a great care is required in
design and development of computer systems.
Computers require use of sophisticated equipment and support facilities. For example, a person solving a problem
of math’s using just a pen and paper can carry these with him or her anywhere with ease. However if the same
problem is to be solved using a computer, the person will not only need access to a suitable computer, it will also be
necessary to have the required software and suitable electric power to run the computer.
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Chapter 5
Types
Computers can be broadly classified by their speed and computer power
Serial .No. Type Specifications
1 PC It is a single user computer having moderately powerful microprocessor
2 WorkStation It is also a single user computer system which is similar to personal computer but have more powerful
microprocessor.
3 Mini
Computer It is a multi-user computer system which is capable of supporting hundreds of users simultaneously.
4 Main Frame It is a multi-user computer system which is capable of supporting hundreds of users simultaneously.
Software technology is different from minicomputer.
5 Supercomputer It is an extremely fast computer which can execute hundreds of millions of instructions per second.
5.1 PC (Personal Computer)
A PC can be defined as a small, relatively inexpensive computer designed for an individual user. PCs are based on the
microprocessor technology that enables manufacturers to put an entire CPU on one chip. Businesses use personal computers
for word processing, accounting, desktop publishing, and for running spreadsheet and database management applications. At
home, the most popular use for personal computers is playing games and surfing Internet. Although personal computers are
designed as single-user systems, these systems are normally linked together to form a network. In terms of power, now-a-
days High-end models of the Macintosh and PC offer the same computing power and graphics capability as low-end
workstations by Sun Microsystems, Hewlett-Packard, and Dell.
5.2 Workstation
Workstation is a computer used for application (CAD/CAM), desktop publishing, software development, and other such
types of applications which require a moderate amount of computing power and relatively high quality graphics capabilities.
Workstations generally come with a large, high-resolution graphics screen, large amount of RAM, inbuilt network support,
and a graphical user interface. Most workstations also have a mass storage device such as a disk drive, but a special type of
workstation, called a diskless workstation, comes without a disk drive. Common operating systems for workstations are
UNIX and Windows NT. Like PC, Workstations are also single-user computers like PC but are typically linked together to
form a local-area network, although they can also be used as stand-alone systems.
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5.3 Minicomputer
It is a midsize multi-processing system capable of supporting up to 250 users simultaneously. A minicomputer, or
colloquially mini, is a class of smaller computers that developed in the mid-1960s and sold for much less than mainframe
and
mid-size from IBM and its direct competitors.
5.4 Mainframe
Mainframe is very large in size and is an expensive computer capable of supporting hundreds or even thousands of users
simultaneously. Mainframe executes many programs concurrently and supports many simultaneous execution of programs
5.5 Supercomputer
Supercomputers are one of the fastest computers currently available. Supercomputers are very expensive and are employed
for specialized applications that require immense amount of mathematical calculations (number crunching). For example,
weather forecasting, scientific simulations, (animated) graphics, fluid dynamic calculations, nuclear energy research,
electronic design, and analysis of geological data (e.g. in petrochemical prospecting).
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Chapter 6
History and
Generation
6.1 History
One of the earliest machines designed to assist people in calculations was the abacus which is still being used some 5000
years after its invention. In 1642 Blaise Pascal (a famous French mathematician) invented an adding machine based on
mechanical gears in which numbers were represented by the cogs on the wheels. Englishman, Charles Babbage, invented in
the 1830's a "Difference Engine" made out of brass and pewter rods and gears, and also designed a further device which he
called an "Analytical Engine". His design contained the five key characteristics of modern computers:-
1. An input device
2. Storage for numbers waiting to be processed
3. A processor or number calculator
4. A unit to control the task and the sequence of its calculations
5. An output device
Augusta Ada Byron (later Countess of Lovelace) was an associate of Babbage who has become known as the first computer
programmer. An American, Herman Hollerith, developed (around 1890) the first electrically driven device. It utilized
punched cards and metal rods which passed through the holes to close an electrical circuit and thus cause a counter to
advance. This machine was able to complete the calculation of the 1890 U.S. census in 6 weeks compared with 7 1/2 years
for the 1880 census which was manually counted. In 1936 Howard Aiken of Harvard University convinced Thomas Watson
of IBM to invest $1 million in the development of an electromechanical version of Babbage's analytical engine. The Harvard
Mark 1 was completed in 1944 and was 8 feet high and 55 feet long. At about the same time (the late 1930's) John Atanasoff
of Iowa State University and his assistant Clifford Berry built the first digital computer that worked electronically, the ABC
(Atanasoff-Berry Computer). This machine was basically a small calculator. In 1943, as part of the British war effort, a series
of vacuum tube based computers (named Colossus) were developed to crack German secret codes. The Colossus Mark 2
series (pictured) consisted of 2400 vacuum tubes.
John Mauchly and J. Presper Eckert of the University of Pennsylvania developed these ideas further by proposing a huge
machine consisting of 18,000 vacuum tubes. ENIAC (Electronic Numerical Integrator and Computer) was born in 1946. It
was a huge machine with a huge power requirement and two major disadvantages. Maintenance was extremely difficult as
the tubes broke down regularly and had to be replaced, and also there was a big problem with overheating. The most
important limitation, however, was that every time a new task needed to be performed the machine need to be rewired. In
other words programming was carried out with a soldering iron. In the late 1940's John von Neumann (at the time a special
consultant to the ENIAC team) developed the EDVAC (Electronic Discrete Variable Automatic Computer) which pioneered
the "stored program concept". This allowed programs to be read into the computer and so gave birth to the age of general-
purpose computers.
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6.2 The Generations of Computers
It used to be quite popular to refer to computers as belonging to one of several "generations" of computer. These generations
are:-
The First Generation (1943-1958): This generation is often described as starting with the delivery of the first commercial
computer to a business client. This happened in 1951 with the delivery of the UNIVAC to the US Bureau of the Census. This
generation lasted until about the end of the 1950's (although some stayed in operation much longer than that). The main
defining feature of the first generation of computers was that vacuum tubes were used as internal computer components.
Vacuum tubes are generally about 5-10 centimeters in length and the large numbers of them required in computers resulted in
huge and extremely expensive machines that often broke down (as tubes failed).
The Second Generation (1959-1964): In the mid-1950's Bell Labs developed the transistor. Transistors were capable of
performing many of the same tasks as vacuum tubes but were only a fraction of the size. The first transistor-based computer
was produced in 1959. Transistors were not only smaller, enabling computer size to be reduced, but they were faster, more
reliable and consumed less electricity. The other main improvement of this period was the development of computer
languages. Assembler languages or symbolic languages allowed programmers to specify instructions in words (albeit very
cryptic words) which were then translated into a form that the machines could understand (typically series of 0's and 1's:
Binary code). Higher level languages also came into being during this period. Whereas assembler languages had a one-to-one
correspondence between their symbols and actual machine functions, higher level language commands often represent
complex sequences of machine codes. Two higher-level languages developed during this period (FORTRAN and COBOL)
are still in use today though in a much more developed form.
The Third Generation (1965-1970): In 1965 the first integrated circuit (IC) was developed in which a complete circuit of
hundreds of components was able to be placed on a single silicon chip 2 or 3 mm square. Computers using these IC's soon
replaced transistor based machines. Again, one of the major advantages was size, with computers becoming more powerful
and at the same time much smaller and cheaper. Computers thus became accessible to a much larger audience. An added
advantage of smaller size is that electrical signals have much shorter distances to travel and so the speed of computers
increased. Another feature of this period is that computer software became much more powerful and flexible and for the first
time more than one program could share the computer's resources at the same time (multi-tasking). The majority of
programming languages used today is often referred to as 3GL's (3rd generation languages) even though some of them
originated during the 2nd generation.
The Fourth Generation (1971-present): The boundary between the third and fourth generations is not very clear-cut at all.
Most of the developments since the mid 1960's can be seen as part of a continuum of gradual miniaturization. In 1970 large-
scale integration was achieved where the equivalent of thousands of integrated circuits were crammed onto a single silicon
chip. This development again increased computer performance (especially reliability and speed) whilst reducing computer
size and cost. Around this time the first complete general-purpose microprocessor became available on a single chip. In 1975
Very Large Scale Integration (VLSI) took the process one step further. Complete computer central processors could now be
built into one chip. The microcomputer was born. Such chips are far more powerful than ENIAC and are only about 1cm
square whilst ENIAC filled a large building. During this period Fourth Generation Languages (4GL's) have come into
existence. Such languages are a step further removed from the computer hardware in that they use language much like natural
language. Many database languages can be described as 4GL's. They are generally much easier to learn than are 3GL's.
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The Fifth Generation (the future): The "fifth generation" of computers was defined by the Japanese government in 1980
when they unveiled an optimistic ten-year plan to produce the next generation of computers. This was an interesting plan for
two reasons. Firstly, it is not at all really clear what the fourth generation is, or even whether the third generation had finished
yet. Secondly, it was an attempt to define a generation of computers before they had come into existence. The main
requirements of the 5G machines were that they incorporate the features of Artificial Intelligence, Expert Systems, and
Natural Language. The goal was to produce machines that are capable of performing tasks in similar ways to humans, are
capable of learning, and are capable of interacting with humans in natural language and preferably using both speech input
(speech recognition) and speech output (speech synthesis). Such goals are obviously of interest to linguists and speech
scientists as natural language and speech processing are key components of the definition. As you may have guessed, this
goal has not yet been fully realized, although significant progress has been made towards various aspects of these goals.
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References:
Basic Computer, Components, importance and Limitation, Types- Wikipedia.org
History and Generation -History and generation: http://clas.mq.edu.au/speech/synthesis/history_computers/