Computer Fundamentals
&
Component Identification
Ogunniran Stephen T.
Table of Content
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Definition of Computer
Forms of Computer
Computer Generation
Structure of a Computer
Component Identification
Types of Computer
Working Computer System
Computer Application
Advantages & Disadvantages of Computer
Definitions
Computer is an electronic data
processing device, which does the
following:
 Accept and store an input data.
 Process the data input.
 And output the processed data in
the required format.
Any electronic device that can
be programmed to accept
data (Input), process the data
into useful information
(output), and store it away (in
a secondary storage device)
for safe keeping or later use.
Computer is an advanced
electronic device that takes raw
data as input from the user and
processes these data under the
control of set of instructions
(called program) and gives the
result (output) and saves output
for future use.
Forms of Computer
Analogue
Digital
Hybrid
Analogue: A form of computer
which accept data as a quantity
(continuous values) over a length of
time. They are used for scientific
purposes. They can be compared to
measuring instruments such as the
thermometer, speedometer /
tachometer used in plants and
refineries.
A practical example that is still widely
used is the Distributed Control
System (DCS) is a computerized
control system used to control the
production line in the industry .
DCS is a dedicated system used to
control manufacturing processes that
are continuous or batch-oriented,
such as oil refining, petrochemicals,
Power Generation etc.
A DCS typically uses custom
designed processors as
controllers and uses both
proprietary interconnections and
communications protocol
(TCP/IP) for communication.
Input and output modules form
component parts of the DCS.
OC 6000e DCS (GE)
Digital Computer: Digital
Computers are capable of
performing operations on data
represented in digit or number
form (i.e discrete values). There
advantage over analogue is that
there accuracy level is higher.
Most computer today are digital,
because they carry out logic,
arithmetic and control processes
involving the manipulation of bits,
words
/
characters
or
information.
Hybrid Computer: A hybrid
computer in a simple term combines
the measuring capabilities of the
analogue with the logic, arithmetic
and control capabilities of the digital
computer. They are usually designed
to perform specific tasks and are
widely used in space vehicle
simulations and training of space and
airline pilots.
Generation & Description
First Generation
The period of first generation: 19461959.Vacuum tube based.
 Second Generation (minicomputer)
The period of second generation:
1959-1965. Transistor based.
 Third Generation
The period of third generation: 19651971. Integrated Circuit based.
•
 Fourth
Generation
The period of fourth generation:
1971-1980.VLSI (very large scale
integrated) microprocessor based.
 Fifth
Generation
The period of fifth generation: 1980onwards. ULSI (ultra large scale
integrated) microprocessor based
-
(Dual Core processors generation
Core i3 – i7)
STRUCTURE OF A
COMPUTER
INPUT UNIT

This unit contain devices with which we
enter data into computer.
It makes the link between user and the
computer possible by translating the
human information into the form which
the computer understands.
such devices include: Keyboard, Mouse,
Scanners, Finger Print Sensor, Camera …
MEMORY / STORAGE UNIT
Memory Or Storage Unit:
This unit can store instructions, data
and intermediate results. It supplies
information to the other units of the
computer when needed. It is also
known as internal storage unit or
main memory or primary storage or
Random access memory(RAM).
The Computer system uses two
type of storage namely: Primary
and Secondary storage.
The CPU interacts closely with
primary storage or main memory
(RAM).
A computer's memory holds data
only temporarily at the time the
computer is executing a program.
ARITHMETIC UNIT
This section performs
arithmetic operations like
addition, subtraction,
multiplication and division.
LOGIC UNIT
This section performs logic
operations such as
comparing, selecting,
matching and merging of
data.
CONTROL
This unit controls the operations
of all parts of the computer.
It does not carry out any data
processing operations.
It’s functions includes:
 Controlling the transfer of data
and instructions among other units
of a computer.
 It
manages and coordinates all the
units of the computer.
 It obtain instructions from the
memory, interprets them and directs
the operation of the computer.
 It communicates with Input / Output
devices for the transfer of data or
results from one storage device to
another.
 It does not process or store data.
OUTPUT
 Video
Display Unit (VDU) or
Monitor
 Printers etc
COMPONENT
IDENTIFICATION
This section briefly
examines all
components required to
assemble a basic PC.
1. CHASIS
Also known as case, houses the
motherboard, power module,
disk drives, adapter cards and any
other physical component in the
system unit. The different types
includes: Tower, Desktop, and
low profile (slim line).
Tower Computer
Desktop Computer
2. Power Module - feeds
electrical power to every
segment in the PC. It converts
Alternating Current (AC) into
Direct Current (DC) which the
computer requires to operate.
3. Motherboard
The motherboard is the core of
the system which
interconnects the various
components of the computer.
4.Microprocessor
Is the engine of the computer, also
called the Central Processing Unit
(CPU).
The unit of a processor is the
transistor, combination of two or
more transistors is referred to as
Integrated Circuit (IC). Modern
microprocessor (microchip) contain
millions of transistors.
MICROPROCESSOR
Microprocessor is a
multipurpose, programmable device
that accepts digital data as input,
processes it according to instructions
stored in its memory and provides
results as output. Microprocessors
operate on numbers and symbols
represented in the binary numeral
system.
Makers of Processors
AMD, Analogue Device, Appolo,
Hewlett-Packard, Hitachi, IBM,
Intel, NEC, OpenCores, Oracle
Corporation (former sun
Microsystems), Texas Instruments,
Western Digital etc
The processor used in a computer
system determines the :
a. Memory size to be used.
b. Speed of the computer.
c. Size / Speed of the cooling fan or
the need for it (2nd Gen 80286 did
not require fan).
d. Power consumption - aiming at
usage in laptops ( 3rd Gen).
e. Cost of the computer
Memory (RAM)
This memory is volatile, referred to as
Random Access Memory (RAM).
It is the primary memory which
holds all programs and data the
processor is using at a given time.
RAM requires power to maintain
storage. So when power is turned off,
everything in RAM is cleared; and
has to be released (from the cache)
when power is turned on.
Cache
A CPU cache is a cache used by
the central processing unit of
a computer to reduce the
average time to access memory.
The cache stores copies of the
data from frequently used main
memory locations.
The initial programs for the
processors come from a special
memory called Read Only
Memory (ROM) which is not
erased when power goes off.
Video Card
The video card controls the
information displayed on
the VDU.
Sound Card
CMOS Battery
CMOS is Complementary Metal
Oxide Semiconductor. It is
responsible for keeping the
certain computer setting such as
the time and date running even
when the computer is not in use.
a. Cooling Fan
Ethernet Card
Wireless Card
Disc Drive
HDD
- Hard Disc Drive ( IDE / SATA)
IDE – Integrated Drive Electronics (a standard
electronic interface used between a computer motherboard's data paths
or bus and the computer's disk storage devices).
SATA – (Serial ATA (Advanced Technology Attachment) is
a computer bus interface that connects host bus adapters to mass
storage devices such as hard disk drives and optical drives.
The recent development is the Solid State
HDD.
Solid-State Drive
A solid-state drive (SSD) (also
known as a solid-state disk or
electronic disk, though it contains
no actual "disk" of any kind, or
motors to "drive" the disks) is a data
storage device using integrated
circuit assembled as memory to
store data.
SSD technology uses
electronic interfaces
compatible with traditional
block input/output (I/O) hard
disk drives, thus permitting
simple replacement in
common applications.
Advantage of SSD over HDD
SSDs and HDDs do the same job: They
boot the system, store applications, and
store files. But each type of storage has its
own unique feature. The advantages are :
1. Speed : SSD will boot in seconds i.e
faster than HDD, hence increases the
overall speed of the PC’s performance.
2. Fragmentation: Files are stored on its
chip, even when the drive space is filled
up its performance is not affected.
3. Durability: An SSD has no
moving parts, so it is more likely
to keep your data safe in the
event that a drive, PC or laptop
drops or is shaken while in use.
SSD is best used by Site
Engineers or by a rough handler
of equipment.
4. Form Factors: Because
HDDs rely on spinning platters,
there is a limit to how small they
can be manufactured.
5. Noise: Even the quietest HDD
will emit a bit of noise when it is
in use from the drive spinning or
the read arm moving back and
forth,
particularly if it's in a system
that's been banged about or in an
all-metal system where it's been
shoddily installed. Faster hard
drives will make more noise than
slower ones. SSDs make virtually
no noise at all, since they're nonmechanical but electronic.
Disadvantages of SSD
1.
Price : SSD’s are quit expensive,
for a 1TB internal 2.5-inch drive,
HDD cost about $100 (i.e)
N16,000 while its SSD equivalent
goes for $600 (N96,000).
CD/DVD - R & RW
CD - Compact Disc
 DVD- Digital Versatile Disc (formerly
Digital Video Disc

Connectors
PS/2 - A Personal System/2 (PS/2)
connector is a 6-pin connector used to
connect peripheral devices, usually a
mouse or keyboard to a computer via the
motherboard.
USB PS/2
VGA Port
IDE to SATA
SATA connector for HDD
PS/2 USB
IDE connecting cable
Types of Computer
Until recently computers were
basically classified as microcomputer,
minicomputers and mainframes
because of their physical sizes and
CPU technology among other
factors. However, technology is
changing and all computers now uses
microprocessors as their CPU
which accounts for their
speed and computing power.
1. Microcomputer
A microcomputer is a complete computer
on a smaller scale and is generally a
synonym for , personal computer or PC ,
a computer designed for an individual.
A PC (as it is now called) is
small, relatively inexpensive
computer designed for an
individual user for wordprocessing, accounting, desktop
publishing, and for running
spreadsheet and database
management applications, e.t.c
At home, the most popular use
for personal computers is for
playing games and surfing the
Internet.
2. WorkStation
Workstation is a computer used for
engineering applications such as
Computer Aided Design / Computer
Aided Manufacturing (CAD/CAM),
desktop publishing, software
development, and other types of
applications, which require a
moderate amount of computing
power and relatively high quality
graphics capabilities.
Workstations generally come with:
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A large, high-resolution graphics screen,
Large amount of RAM
Inbuilt network support
A graphical user interface
A mass storage device such as a disk drive
NAS (Network Attached Storage)
A special type of workstation, called a
diskless workstation, comes without a
disk drive. E.g Thin Client.
3. Minicomputer
The term "minicomputer
"evolved in the 1960s to
describe the smaller
computers that became
possible with the use
of transistor technologies.
Transistors
Minicomputer (with the advent of chip)
 It is a midsize computer.
A minicomputer is a multiprocessing system capable of
supporting up to 250 users
simultaneously. A minicomputer,
(a term no longer used) is
a computer of a size intermediate
between a microcomputer and
a mainframe.
Typically, minicomputers have been
stand-alone computers (computer
systems with attached terminals and
other devices) sold to small and midsize businesses for general business
applications and to large enterprises
for department-level operations. In
recent years,
The minicomputer has evolved into
the "mid-range server"
`
A
high processing speed
 Improved GUI
 Multiple CPU …
4. Mainframe computer
Mainframe is a very large in size and
expensive computer capable of
supporting thousands of users
simultaneously.
Mainframe executes many
programs concurrently.
Mainframes support many
simultaneous programs execution.
Mainframe computer ( before)
Mainframe computer ( now)
The types of computer deployed
in Data Centers can be referred
to as “mainframe computer” and
can be located remotely from the
users.
5. Supercomputer
Supercomputers are one of the
fastest computers currently
available. They are :
 Very expensive and are deployed
for specialized applications that
require large 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).
WORKING COMPUTER
SYSTEM
A working computer system
is made up of computer
hardware and software.
APPLICATION
SOFTWARE
SYSTEM SOFTWARE
COMPUTER HARDWARE
HARDWARE & SOFTWARE
Hardware: Refer to the physical
units that make up the computer
system. Any other physical
attachment (peripherals) would
also be part of the hardware.
The hardware on its own is nonfunctional. It normally requires
the software to work.
 Software
Refer to any program
designed to assist users to make
best use of their hardware.
Computer software are therefore
the programs that run on the
computer hardware, enabling the
system to perform specific tasks
for the end users.
- System Software - is a computer
software designed to operate and
control the computer hardware and
to provide a platform for running
application software. They are
sequence of instructions, written in a
language which the computer
understands e.g Windows, Linux,
Android, Mac etc
- Application software is any software
created for a specific purpose. Typically it
is based on customer’s requirement.
Examples of such are:
- Microsoft Office - for office processes
- Corel - for graphics and design
- AutoCAD – for Architectural drawings
& design
- NAAPS, Peachtree – for accounting
purposes .
- DHML Enrollment Application etc
Computer Application
The use of computer has become
part of our day to day life, ranging
from electronic calculator,
mobile phones, ipod, home
electronics, etc. Hence computer
application is growing each.
Business
Computer is used in business
organisation for:
 Payroll Calculations
 Budgeting
 Sales Analysis
 Financial forecasting
 Managing employees database
etc.
Banking
 On-line
banking is possible via
the use of computer.
 ATM machines makes it easier
for customers to deal with
banks.
Insurance
 Insurance
companies keep all
records with the use of
Computer.
 Insurance Companies are
maintaining a database of all
clients with information showing:
how to continue with policies
 starting date of the policies
 next due installment of a policy
 maturity date
 interests due
 survival benefits
 bonus

Education
 The
computer has provided a lot of
facilities in the Education System.
 The uses of computer provide a tool
in the Education system known as
CBE (Computer Based Education).
 CBE involves Control, Delivery and
Evaluation of learning.
 The
computer education is very
familiar and rapidly increasing the
graph of computer students.
 There are number of methods in
which educational institutions can
use computer to educate the
students.
 It is used for prepare a database
about student performance and
analyses are carried out.
Marketing
 Advertising: With
computers,
advertising professionals create
art and graphics, write and revise
copy, and print and disseminate
ads with the goal of selling more
products.
At Home Shopping: Home
shopping has been made possible
through use of computerized
catalogues that provide access to
product information and permit
direct entry of orders to be filled
by the customers.
Health Care
Computers are being used in hospitals to
keep the record of patients and
medicines. It is also used in scanning and
diagnosing different diseases. ECG, EEG,
Ultrasounds and CT Scans are also done
by computerized machines.
 Some of major fields of health care in
which computers are used:

 Diagnostic
System: Computers
are used to collect data and
identify cause of illness.
 Lab-diagnostic
System: All tests
can be done and reports are
prepared by computer.
 Patient
Monitoring
System: These are used to check
patient's signs for abnormality such
as in Cardiac Arrest, ECG, etc.
 Pharma Information
System: Computer checks DrugLabels, Expiry dates, harmful drug
side effects etc.
 Nowadays, computers are also
used in performing surgery.
Engineering Design
One of major areas is CAD (Computer
a’;ided design). CAD provides creation,
edition, and modification of image. Some
fields are:
 Structural Engineering: Requires
stress and strain analysis required for
design of Ships, Buildings, Bridges,
Airplanes, etc.
Industrial Engineering
Computers deal with design,
implementation and
improvement of Integrated
systems of people, materials and
equipments.
Advantages of Computer
HIGH SPEED
 Computer is a very fast device.
 It is capable of performing addition of
very big data.
 The computer has units of speed in
microsecond, nanosecond and even the
picosecond.
 It can perform millions of calculations in a
few seconds as compared to man, who
can spend many months for doing the
same task.
ACCURACY
 In
addition to being very fast,
computers are very accurate.
 Computers perform all jobs
with 100% accuracy.
STORAGE CAPABILITY

Memory is a very important characteristic
of computers. The computer has much
more storage capacity than human beings.
It can store large amount of data.
It can store any type of data such as
images, videos, text, audio and any other
type.
DILIGENCE
 Unlike
humans, a computer is free
from monotony, tiredness and lack
of concentration.
 It can work continuously without
creating any error and boredom.
 It can do repeated work with same
speed and accuracy.
VERSATILITY
A computer is a very versatile machine.
 A computer is very flexible in performing
the jobs to be done.
 This machine can be used to solve the
problems relating to different fields.
 At one instant, it may be solving a
complex scientific problem and the very
next moment it may be playing a card
game.

RELIABILITY
A
computer is a reliable machine.
 Modern electronic components
have failure-free long lives.
 Computers are designed to make
maintenance easy.
AUTOMATION
 Computer
is an automatic machine.
 Automation means ability to perform
the task automatically.
 Once a program is given to
computer, i.e. stored in computer
memory, the program and
instructions can control the program
execution without human interaction
(as in auto-pilot)
REDUCTION IN PAPER WORK
 The
use of computers for data
processing in an organization leads to
reduction in paper work and speeds
up the process.
 As data in electronic files can be
retrieved when required, the
problem of maintenance of large
number of files gets reduced.
REDUCTION IN COST
 Though
the initial investment for
installing a computer is high but it
substantially reduces the cost of
each of its transaction.
Disadvantages
NO IQ
 A computer is a machine and has no
intelligence of its own to perform any
task.
 Each and every instruction has to be given
to the computer.
 A computer can not take any decision on
its own.
DEPENDENCY
 It
can perform function as
instructed by user, so it is fully
dependent on human being.
ENVIRONMENT
 The
operating environment of
computer should be dust-free
and suitable to it.
NO FEELING
 Computer
has no feeling or
emotions.
 It
cannot make judgement based
on feeling, taste, experience and
knowledge unlike a human being.
Thank you for listening