Module 001 Introduction to Computers

At the end of this module you are expected to:

1. Know the evolution of computers and differentiate the improvement of
computer according to its generation;
2. Determ ine the different developer of computer system during the
evolution phase;
3. Identity the mea ning of computer and enumerate the four part~ of
computer system;
4. Determine the capahilities, li mitations and different uses of computer.

Lesson 1: The evolution of computers

When we say computer it is intended by a person knowledgeable about performing a
basic mathematical calculation with the help of any computing devices.
It was in the year 1930's when the evolution of the computer started. While the
history of the computer started when the first mechanical adding machine was invented in
1642.
The first mechanical adding machine is an abacus. An Abacus or also known as a
calculating frame is a calculating machi ne capable of performing arithmetic processes. The
logarithm idea was invented by john Napier while the invention of slide rules was invented
by William Oughtred. Today, an abacus is constructed with a bead that can be slide in a
bamboo stick or wires. The person who uses an abacus is called Abacist.
First Generation (Vacuum Tubes) 1939 - 1954
The evolution of computers is divided into five generations. The computers in the first
generation were expensive and bulky. Vacuum tubes use a machine language for computing
and can only solve a problem one at a time. Computers duri ng this phase cannot support
multitasking task. Below are the lists of computers invented during the first generation
phase.
Vacuum Tubes
A vacuum tube, or also known as "electron tube" in North America,
"thermionic valve", or "valve" in Britain is a device used to amplifY, switch,
otherwise modifY, or develop an electrical signal that controls the movement of
electrons in a low-pr essure space.
 ABC
The ABC or also known as Atanasoff Berry Computer in November 1939
was developed by John V. Atanasoff in 1937called as the first electronic computer.

Z Machine
The Z machine was the first mach ine capable of accepting binary and floating
numbers and invention of Konrad Zuse in 1941.

EN lAC
The Electronic Numerical Integr ator and Calculator (ENIAC) is the first
general purpose electronic computer. The ENlAC is capable of sto ring and saving
programs. This is an invention of Vonn Neumann at the United States (U.S) Army's
Ballistic Research Laborato ry in 1946.

Second Generation (Punched card I transistor) 1954- 1959

With invention of transistors computers in the third generation became smaller and
cheaper.
Punch Card
A "punch card" or "punched card" or "punchcard" or "Hollerith card" or "IB M
card", this is represented by a piece of paper that may contain digital information
represented by a hole in a predefined position. Early computing uses a punch card as
a medium of inputs both for computer programs and data.

ERMA
ERMA or also known as Electronic Recording Machine Accou nting is a project
of Stanford Research Institute. The primary function of ERMA is to automate the
bookkeeping process. In 1959 ERMA was delivered to the Bank of Bank of America in
California, a pioneering bank company that uses the ERMA.

Third Generation (Chip I Integrated Circuit (IC)) 1959 - 1971

In the 3rd generat ions. the semi-conductors increased the speed and efficiency of the
computer. Operating systems were developed, monitors and keyboards become popular as
the input and output devices. With this inventions, the scientist has thought of a possible way
on how they could speed up the computer operations as well as offer the computer that not
so bulky. This is the reason why the integrated Circuit or also known as IC has been
developed.
Nowadays. Integrated circuits or IC are used in almost all electronic equ ipment and have
modernized the world of electronics.
 POP·8
DEC company launch the PDP-8 the first minicomputer in 1968. After
launching the PDP·8, the development of ARPANET began in in the following year
1969 where the financial backing of the department of defense has started.

Fourth Generation (Microprocessor) 1971·1991

1972, Intel introduced the 8080 microprocessor. A microprocessor primary
function is to integrates all of a central processing unit (CPU) capability on a single integrated
circuit or IC

Fifth Generation (Under the development) 1991 -beyond

Computer system under the fifth generation is going to be based on principles of
Artificial Intelligence and Natural Language recognition.

Lesson 1: What is a computer?

A computer is the Central Processing Unit (also known as CPU) that execute programs
or tasks. The power of the computer depends on its specificatio ns.
A program is simply a li st of instructions preordained to be followed mechanically by a
computer. A computer is developed to carry out instruction written in a simple language called
machine language.
Main memory is consists of a sequence of locations. The location in the main memory are
numbered, and this number is called the address. See figure below for reference.

Central Processing Unit

CENTRAl PROCESSOR
ALU cu
{Amtlmetlc Logic unn) {Control un•)
ltNPUT ~~ r··-··-·-··-··--·---·-~ . . . . .- . . -·------··- lourPur ~I
MEMORY UNIT
4-··--········----i··-····-········-·---...
•• •
----------------
ROM • RAM •• CACHE

~TORAG§
 Figure 1.0 ·Central Processing Unit
Retrievedfrom: https: f/www.webopedia.com,ITERM/CICPU.html
Retrieved: August 13, 2018

Machine language instructions are expressed as binary numbers. A binary number is consist
of two digits. the zeros and ones. So, a machine language instruction is just a sequence of zeros and
ones. Each particular sequence the zeros, and one read some particular instruction according to the
binaty number read by the computer.

Data consist of individual facts or bits of information, which by themselves may not make sense
to a person. Machine language instructions are expressed as binary numbers. A binary number is
made up of just two possible digits, zero and one. So, a machine language instruction is just a
sequence of zeros and ones. Each particular sequence encodes some particular instruction.

Four parts of Computer

1. Hardware · The physical parts that make up the computer are called hardware.
Hardware is the tangible parts of the computerthat you can touch. The hardware
part of a computer is consist of interconnected electronic devices that are use to
control the computer operations like input and output.
2. Software • Software is the set of instruction that makes the computer perform
tasks.
3. People· are the computer operator, also known as users.
4. Data consist of individual facts or bits of information, which by themselves may
not make sense to a person. The computer reads and stores data of all kinds
whether words, numbers, images or sounds in the form of numbers. Following
instructions from the software and the user, the computer manipulates data by
performing calculations, doing a comparison, or arranging the bits of information
so they make sense to the users.

Capabilities and Limitations of Computer

Capabilities of Computer:
1. The computer has the ability to perform arithmetic operation like: addition,
subtraction, multiplication division, ete. The computer is basically developed to
help solve complicated mathematical formulas using large volumes of data. It can
perform this task at high speed and with great precision.
2. The computer can perform logical operations. Given the correct instruction, it
can determine whether a value (number or an alphabetic character or combination
of both) is greater than, equal to or less than another value. Based on the result of the
comparison it can be instructed to choose among alternative instructions to be
undertaken, which in a way is equivalent to making decision.
3. The computer has the ability to store and retrieve information because a
computer has a storage area called memory. The computer has memory, a storage
area. Data accepted by the computer is kept in this area for processing. The computer
is able to store a large amount of data and, by series of instructions, be able to retrieve
these data many times when needed.
4. The computer has the ability to process information at a very higb speed. If
pencil and paper have to be used to process a large volume of data, a Iotti me is needed
to finish the task. With computers, whether it is comparing, calculating, or arranging
data, processing time takes only a minutes or even a second.
S. The computer can direct itself in a predetermine manner without human
intervention. When the computer is performing task, it is actually following
instructions laid out in a program. A program contains a set of instructions used by
the computer to perform a specific job.

Limitations of Computer
1. Computers do not think for you.
A computer functions only when it is provided the input information it needs.
Input data provided to the computer has to be precise, objective and correct for it to
produce the required result. Instruction that the computer will have to follow must
be specific, detailed and defined for processing to be correct. If you input the wrong
data, or give a wrong set of instructions to the computer, definitely the computer will
produced the wrong result.
z. The computer cannot correct Inaccurate data.
The computer cannot decide whether data is correct or not, unless alternatives
are given in advance in the form instructions. Data must therefore be verified and
co~rected before being entered to make sure that what fed to computer is correct.

3. The computer is subject to breakdown.

The computer cannot completely avoid making errors which usually occur
when there is tluctuation in the electric current, when an electrical component or part
is malfunctioning or when the computer is over heated it is the same as other
machines which need constant care and maintenance.

Uses of Computer
The uses of computer classified into six categories:
1. Personal Computing
2. Science and Research
3. Information System J Data Processing
4. Education
5. Medicine
6. Artificial Intelligence
A. Personal Computing
The small computer called microcomputer can be controlled by a single
person, thus the term "personal computing". At home. these computers can be used
for applications like: maintaining up· to-date inventory of household items, storing
names and addresses, creating and mon itoring a household budget, keeping an
appointment and social calendar, writing letters, education and entertainment such
as computer games.
In small businesses, computers can be used for word processing. desktop
publishing, electronic spreadsheet, and maintaining databases.
B. Word processing is a software that allows users to enter, store, manipulate and
print text (letters, reports, etc).
C. Desktop publishing is a software that allow users to produce near type -set-
quality copy of newsletter, advertisements, and other publishing jobs.
D. Electronic spreadsheet is a software that permits users to work with numbers
formatted in lines and columns normally used for accounting jobs.
E. Database permits users to create and maintain several ftles and extract in an easy
convenient manner.
F. Science and Research
Engineers and scientist use computers as a tool in experimentation and design.
Aerospace engineers use computer to simulate the effects of wind tunnel to analyze
the aerodynamics of an airplane prototype. Chemist use computer graphics to create
three (3) dimensional views of an experiment molecule.
G. Information System I Data processing
Computers are used to support the administrative aspects of an organization,
for example: applications including payroll system, airline reservation system,
grading system and others. They provide for fast data processing requirements and
information needed to make better, more informed decisions by managements.
H. Education
Computers can interact with students to enhance the learning process. With
multidimensional communications using sound, print, graphics and color, the
computer has become a good educational tool in the home, in the classroom and in
business. Computers can help children learn to read and write. Adults can also use
computers to learn about just anything from auto mechanics to zoology.
I. Medicine
Tiny "computer on a chip" are being embedded in artificial hearts and other
organs. Once the organs are implanted in the body, the computer monitors critical
inputs, such as blood pressure and flow, then takes corrective action to ensure
stability of operation in a continuous feedback.
J. Artificiallntelligence
Today's computer can imitate many human movements such as reaching,
gasping. calculating, speaking, remembering, comparing numbers and drawings.
Researcher are working to expand these capabilities by developing computers and
programs that can imitate human intelligence. This general area of research is called
artificial intelligence. However. computer can never be capable of simulating the
distinctly human qualities of creativity, humor and emotions.
Lesson 3: Looking inside the computer
4 components of a computer
1. Processor
2. Memory
3. Input J output devices
4. Storage

The Processor
The procedure that transforms raw data into useful information is called
processing. To perform this transformation. the computer uses two components:
The Processor and Memory. The processor is like the brain of the computer, it
organizes and carries out instructions that come from either the user or the software.
In a personal computer, the processor usually consists of one or more
microprocessors (sometimes called chips), which are slivers of silicon or other
material etched with many tiny electronic circuits. To process data or complete an
instructions from a user or a program, the computer passes electricity through the
circuits.
The microprocessor is plugged into the computers motherboard. The
Motherboard is a rigid rectangular card containing the circuitry that connects the
processor to the other hardware. The motherboard is an example of circuit board.
In most personal computers, many internal devices-such as video cards, sound cards,
disk controller, and other devices-are housed on their own smaller circuit is board,
which attach to the motherboa rd.
A personal computer processor is usually a single chip or a set of chips
contained on a circuit board. In some powerful computers, the processor consists of
many chips and the circuit board on which they are mounted. Other term Central
Processing Unit (CPU) refers to a computers processor and people often refer to
computer systems by the type of CPU they contain. A "Pentium 4" system, for example,
uses a Pentium 4 microprocessor as in CPU.

The Memory
Memory is like an electronic scratch pad inside the computer. When you
launch a program, it is loaded into and run from memory. Data used by the program
is also located into memory for fast access. A new data is entered into the computer,
it is also stored in memory-but only temporarily. The most common type of memory
is Random Access Memory (RAM} as a result, the term memory is common ly used
to mean RAM. Data is both written to read from this memory. (For this reason, RAM
is called Read/Write Memory).
 One of the most factor affecting the speed and power of a computer is the
amount of RAM it has. Generally, the more RAM the computer has, the more it can do,
and the faster it can perform a certain task. The most common measurement unit of
memory is the byte-the amount of memory it takes to store a single character, such
as letter of the alphabet or the numeral. When referring to a computers memory, the
number are often so large that it is useful to used terms such as kilobyte(KB),
megabyte(MB),gigabyte(BT),and terabyte(TB) to describe the values.
It is the pa rt of the computer where all computer processing takes place. It
consists of three (3) parts.
1. ALU (Arithmetic Logic Unit)
The ALU perform all arith metic operations and logical processes required to
solve a computer problem.
2. Control Unit
The Control Unit is the little supervisor of the CPU. It directs and coordinates
the Operation of the entire computer according to the instructions laid out in
the program, it interprets the instructions, gets data to be used in each
instructions and relays the appropriate commands to other parts of the
hardware where action is to take place.
3. Memory
This is the storage area of the hardware which contains the program and data
being worked with by the computer. You can also call it ''primary memory" or
"main memory".

The main memory contains two (2) types of memory:

1. ROM (Read Only Memory)
Contain all system programs that are used for start up operations of the computer.
When you buy a computer, these system programs have already been built into
the hardware making it possible for you to use the computer. It is the programs in
ROM that instruct the CPU to read another program from a disk, thus performing
a self-helping start up when the computer is turned-on. Since it hardwired into
the computer, the programs it contains cannot be changed nor deleted.
2. RAM (Random Access Memory)
Stores data that can either be read (retrieved for use in processing) or written to
(store data). It is the computer scratch pad. In most computer the RAM holds:
• The active parts of the operating system, the fundamental program that
control the operation of the computer (example, a payroll program);
• The application program that is being executed;
• Part of all the data used by the application program (example, data being
used in payroll program);
• A representation of the data being shown on the video display.
To describe the RAM, it is non- permanent type of ,memory. meaning to say
that in case you happen to turn-off the computer while sui ng it, all data in RAM will
be erased. There is, of course, a way of storing data almost permanently that is by the
use of storage media.
Input and Output Devices
A computer would be useless if you could nor interact with it because the
machine could not receive instructions or deliver the result of its work. Input devices
accept data and instructions from the user or from another computer system (such
as computer on the internet). Output devices return processed data to the user or to
another computer system.

Input devices
The most common input device is the keyboard, which accepts letters,
numbers, and commands from the user. Another important type of input device is the
mouse, which let you select option from on-screen menus. You use a mouse by
moving it across a flat surface and pressing its buttons.
Other popular input devices are trackballs, touchpad, joysticks, scanner,
digital cameras and m icrophones. The mouse, trackball, and touch pad enable
you to draw or point on the screen. The joystick is especially well suited for playing
fast moving video games. A scanner can copy a printed a graphic page of text into the
computer memory. Digital cameras record live images that can view and edited on
the computer. A microphone or CD player attached to the computer enables you to
add the sound of a voice or a music selection.

Output Devices
The function of an output device is to present processed data to the user, the
most common output device are the monitor and the printer. The computer sends
output to the monitor (the display screen) when the user needs to see the output.
It sends output to the printer when the user request a paper copy-also called a hard
copy-of a document. just as computers can accept sound as input, they can use stereo
speakers or headphones as output devices to produce sound.
Storage
A computer can function with only processing. memory, input and output
devices. The purpose of the storage is to hold data permanently.

You may think of storage is an electronic file cabinet and RAM as an electronic
worktable. When you need to work with a program or a set of data, the computer
locates it in the file cabinet and puts a copy on the table. After you have finished
working with the program or data, you put it back into the file cabinet. The changes
you make to data while working on it replace the original data in the file cabinet
(unless you store it in different place).
 Novice computer users often confuse storage with memory. Although the
function of storage and memory are similar, they work in different ways. There are
three major distinctions between storage and memory.
1. There is more room in storage than memory.
2. Contents are retained in storage when the computer is turned-off, whereas the
program or the data you put into the memory disappear when you shutdown
the computer.
3. Storage is very slow compared to memory, but it is much cheaper than
memory.

There are many types of storage devices including tape drives, optical drives
and removable hard drives. However the most common storage medium is the
magnetic disk.
A disk is a round, flat object that spins around its center. Read/Write heads,
which are similar to the heads of a tape recorder or VCR, are used to read data from
the disk or write data onto the disk
The device that holds a disk is called disk drives. Some disk are built into the
drive and are not meant to be remove, other kinds of drives enables you to remove
and replace disk Most personal computer have at least one removable hard disk (or
hard drive). In addition, there is also diskette drive, which allow you to use
removable diskettes (floppy disks). The hard disk serves as the computers primary
filing cabinet it can store for more data than a diskette can contain.
The CD-ROM drive is another common type of storage device. Compact disk
(COs) are typr of optical device, identical to audio COs. Compact Disk Read Only
Memory (CD-ROM) drive. As the name implies, you cannot change the information
on the disk just as you cannot record over an audio CD.
If you purchase a CO-Recordable drives (CD -R) drive, you have the option
of creating you own COs. A CD-R can write data to and read data from a compact disk.
To create your own compact disk , you must use special CD-R disk, which can be
written on only once. CO-Re-Writable disk, which can be written to a multiple times
An increasingly popular data storage technology is the Digital Video Disk
(DVD), which is revolutionizing home entertainment

References and Supplementary Materials

Books and Journals
1. Denning, Peter).; Martell, Craig H. (2015). Great principles of computing MIT Press
QA 76 03483 2015
2. Oleary, Timothy). (2015). Computing essentials: making IT work for you. QA 76.5 042
2011
Oleary, Timothy).; Oleary, Linda I. (2015). Computing essen rials 2014: making it
work for you WLB McGrawhill QA 76 054 2014
Online Supplementary Reading Materials
1. A brief history od computer;
http:lfpeople.bu.edu/bawsfbrief%20computer%20history.html; August 2, 2018
2. Computer basics; https;f/edu,gcfE!oba!.org/en/computerbasicsfbasjc-~zans-of-a­
computer/1/ ; August 3, 2018
3. Central Processing Unit;
http:/fwww.hhc.co.ukfschoolsfgcsehjtesize/ict/hardware/Oinputandoutputdevicesr
ey3.shtml ; August 3, 2016
Online Instructional Videos
1. The components of computer and their function;
https://www.youtube.com/watch?v- EC fOWfmtPA; August 3, 2018
2. Computer hardware and software; https;//www.youtube.com/watch?y=8UyiMiYQvS4
; August 3, 2018
3. History and generations of computers;
https:f/www.youtube.com/watch?v=xrUvF!WIYCY; August 3, 2018
4. Generations of computers; https;fjwww.youtube.comjwatch?v=sTc4klYUnoA ;
August 3, 2018
5. The central processing unit; https:f/www.youtube.com/watch?v- FZGugFQdr60 ;
August 2, 2018