The document provides an overview of computer hardware, software, classifications, and connectivity devices. It defines a computer and describes its key features. It then discusses computer hardware and software, categorizing hardware as internal or external and describing common software types. The document classifies computers based on size and capacity, purpose, and hardware design. It also defines and provides examples of common peripheral devices for input, output, storage, and connectivity. In closing, it outlines various port types for connecting peripheral devices to computers.

1. By: Gemechis Bido
Connecting Hardware Peripherals
www.gemechisbido.com

2. Content
01 Introduction to Hardware and Software
02 Computer classification
03 Peripheral devices
04 Connectivity devices

3. Acronyms
HW – Hardware
SW – Software
LED – Light Emitting Diodes
CRT – Cathode Ray Tube
LCD – Liquid Crystal Display
CPU – Central Processing Unit
RAM – Random Access Memory
CD – Compact Disk
DVD – Digital Versatile Disk
USB - Universal Serial Bus
OH&S – Organizational Health and Safety
PC - Personal Computer

4. What is Computer?
Computer is an electronic device for storing and processing data, typically in binary
form, according to instructions given to it in a variable program. It has the ability to
store, retrieve, and process data.
Computer is a machine that can be programmed to carry out sequences of arithmetic
or logical operations automatically. Modern digital electronic computers can perform
generic sets of operations known as programs. These programs enables computer to
perform a wide range of task.
➢ Features of Computer
❑ Computer is Programmable.
❑ Convert Data into Information.
❑ It is Digital Electronic Machine.
❑ Execute only Machine Instructions.
❑ Understands only binary (0 OR 1)

5. ✓ Computer hardware is a collection of all the parts you can physically touch.
Computer parts include the physical parts of a computer, such as the case, CPU, RAM,
monitor, keyboard speaker and mouse.
There are two types of computer hardware:
❑ Internal Hardware: Motherboard, hard drive, CD drive, Floppy drive, RAM and FAN.
❑ External Hardware: Monitors, keyboards, mouse, speaker, printers and scanners.
Note: Hardware is used for taking Input data from the user, store the data and display
the Output and execute the commands given by an individual.
Hardware devices are categorized in to Input Devices, Output Devices, Storage Devi
ces and Internal Components and this part is more discussed in the next topic which is
called peripheral devices.
What is Computer Hardware?

6. What is Computer software?
Computer software is a collection of computer programs and related data that provide the
instructions for telling a computer what to do and how to do it.
Software is a conceptual entity which is a set of computer programs, procedures, and
associated documentation concerned with the operation of a data processing system.
Generally, a language that a computer understands. Collection of instructions that enables
a user to interact with the computer
Major types of computer software are:
❑ Application software
❑ System software
❑ Programming software
❑ Driver software

7. Types of Software
❑ Application Software: an application software is designed to handle specific tasks for
users. Such software directs the computer to execute commands given by the user and
may be said to include any program that processes data for a user.
❑ System Software: is a program designed to run a computer’s hardware and application
s and manage its resources, such as its memory, processors, and devices. It also
provides a platform for running application software, and system software is typically
bundled with a computer’s Operating System.
❑ Computer Programming Software: computer programmers use programming software
to write code. Programming software and programming tools enables developers to dev
elop, write, test and debug other software programs.
E.g. Assemblers, compilers, debuggers and interpreters.
❑ Driver Software: in the most fundamental sense, a driver is a software component that
lets the Operating System and a device communicate with each other.

8. Computer
Classifications
We can classify the computers into the following 3
categories:
On the basis of Size and Capacity, [Super Com
puter, Mainframe, Mini, and Micro Computer].
On the basis of Purposes, [General and
Special Purpose].
On the Basis of Hardware Design and Type
[Analog, Digital, and Hybrid Computer].

9. On the Basis of Size: Type of Computer
➢ Super Computer
These are arguably the most powerful in terms of speed and accuracy. They are types of comput
ers used in solving complex mathematical computations. They are capable of executing trillions
of instructions per second, which is calculated in Floating Point Operations Per Second (FLOPS)
. The typical personal computer used at home and the office is only capable of calculating Million
s of Instructions Per Second (MIPS). Supercomputers can go even faster with the rate of Peta F
LOPS (or PFLOPS). This could bring up their processing numbers to the quadrillion.
The operating systems that run in supercomputers vary depending on the manufacturer but are g
enerally based on the Linux Kernel. A few popular ones include: [ CNK OS used in Blue Gene fro
m IBM, Cray Linux Environment used in Titan, Sunway Raise OS in Sunway Taihu Light ]
These computers are the largest in terms of size. They can occupy anything from a few feet to
hundreds of feet. They also don’t come cheap as they can be priced between $200,000 to over $
100 million. For example, weather forecasting requires a supercomputer.

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11. ➢ Mainframes
Mainframe computers are large-sized computer types. They are equally powerful but fall short in
terms of the computation ability in supercomputers. They are like big file servers, enabling
multiple users from nearby and remote locations to access resources at the same time.
Also known as big iron, these systems can handle massive amounts of data going in and out si
multaneously. This makes them popular with businesses.
They are also resilient, as they are capable of operating for over 10 years without failing. Users
access the mainframe using terminals or personal computers. This can happen within the same
building or via a wide area network (WAN).
Most of these systems run the z/OS (operating system) on 64bit architecture.
❑ IBM System z9 mainframe is a large size computer type
They are used in large organizations where thousands of clients have to access data simultane
ously. For example: Performing ATM cash withdrawals and deposits.

12. Mainframe Computer

13. ➢ Minicomputers
Minicomputers are general-purpose devices without the monumental expenses associated with
a larger system. Their processing power is below that of mainframe systems but above the
capabilities of personal computers. Also known as mid-range computers, these became popula
r in the late 1960s but have become almost extinct because of the popularity of personal
computers. The latter can now perform most of the tasks reserved for minis.
Minicomputers were intended for a number of activities listed below:
❑ Switchboard control.
❑ Dedicated applications for graphics and computer design.
❑ Time-sharing, to allow multiple users to interact concurrently on a single system.
❑ Control and monitoring of manufacturing activities.
❑ Monitoring and control of laboratory equipment.

14. Mini Computer
D LL

15. ➢ Servers
These are types of computers used to provide resources, services, and functionality to client
computers in a server-client network model. Resources provided are based on the functio
ns of a particular server, which may fall under these categories:
[ File server, Database server, Print server, FTP servers, Application server, Webserver ]
Their sizes will depend on the purpose and tasks in the network. Of course, bigger and mor
e multitasking installations will require multiple systems and storage installations.
A common errant is that desktop systems can be used as servers. Far from it, true server
systems are specialized computers with abilities far beyond what personal computers can
deliver.
✓ Servers are optimized to run 24 hours and are capable of hot-swapping of storage and
other hardware without having to shut down the system.

16. Server Computers
DELL
HP

17. On the Basis of Hardware Design

18. Peripheral Devices
Any device connected internally or externally to a computer system unit and used in the transf
er of data as well as processing information is considered as peripheral devices.
Any input, output or external storage device connected externally or internally communicate w
ith the computer's processors is termed as peripherals. Examples are: monitor, keyboard, pri
nter, disk, tape, graphics tablet, scanner, joy stick, paddle or mouse etc.
Categories of Peripherals and Device Drivers
Peripheral devices can be categorized in to three,
1) Input device,
2) Output devices and
3) Internal and external storage devices.
➢ Input device - is a device that has been used as a means of input. It is any peripheral (pie
ce of computer hardware equipment) used to provide data and control signals to an infor
mation processing system such as a computer or other information appliance. The commo
n input devices are keyboard, mouse, and scanner.

19. ▪ Keyboard: The computer key board is used to input, or
enter, letters, numbers, symbols, punctuations and comma
nds into the computer.
The standard keyboard layout is sometimes called QWERTY
layout and it is the most common layout.
▪ Mouse: is any human interface device that allows a user to
input spatial data to a computer. In the case of mice and to
uch screens, this is usually achieved by detecting moveme
nt across a physical surface.
The most familiar type of mouse is Optical mouse and this kind
of mouse utilizes light-emitting diodes (LED) or laser as a meth
od of tracking movement
Input Devices

20. ➢ Scanner: is a device that can scan or digitize
images on paper and convert them to data that
the computer can use. They can then be stored
in a file, displayed on the screen, added to docu
ments, or manipulated.
➢ Imaging and Video input Devices: Video
input devices are used to digitize images or vid
eo from the outside world into the computer. Th
e information can be stored in a multitude of for
mats depending on the user's requirement.

21. Output Device
An output device is any piece of computer hardware equipment used to communicate the res
ults of data processing carried out by an information processing system (such as a computer)
to the outside world. In computing, input/output, or I/O, refers to the communication between
an information processing system (such as a computer), and the outside world. Examples of
output devices are:-
Printer
In computing, a printer is a peripheral which p
roduces a text and/or graphics of documents
stored in electronic form, usually on physical
print media such as paper or transparencies.

22. Speakers:
Computer speakers range widely in quality and in
price. The computer speakers typically packaged
with computer systems are small, plastic, and
have mediocre sound quality. Some computer
speakers have equalization features such as bass
and treble controls.
Headphones:
Headphones are a pair of small loudspeakers, or
less commonly a single speaker, held close to a
user's ears and connected to a signal source suc
h as an audio amplifier, radio, CD player or portab
le media player.

23. A monitor or display (sometimes called a visual displa
y unit) is an electronic visual display for computers. Th
e monitor comprises the display device, circuitry, and
an enclosure.
The display device in modern monitors is typically a thi
n film transistor Liquid Crystal Display (TFT-LCD) thin
panel, while older monitors use a cathode ray tube ab
out as deep as the screen size.
The first computer monitors used Cathode Ray Tubes
(CRTs), which was the dominant technology until they
were replaced by LCD monitors in the 21st Century.
LED
Light Emitting Diode
LCD
Liquid Crystal Display
CRT
Cathode Ray Tubes
Monitor

24. Storage Devices
Computer data storage, often called storage or memory, refers to computer componen
ts and recording media that retain digital data. Data storage is one of the core functions a
nd fundamental components of computers. There are 3 types of storage devices:
Primary Storage: is also known as the main memory
or a temporary storage device. It is fast in nature but can
accommodate only few data. Data that has been stored i
n memory flushes off when you restart your computer, th
us called temporary storage device.
It is the only one directly accessible to the CPU.
The CPU continuously reads instructions stored there an
d executes them as required. Any data actively operated
on is also stored there in uniform manner.

25. Secondary Storage
Secondary storage (also known as external memory or auxiliary storage), differs from prim
ary storage in that it is not directly accessible by the CPU. The computer usually uses its
input/output channels to access secondary storage and transfers the desired data using in
termediate area in primary storage. Secondary storage does not lose the data when the de
vice is powered down—it is non-volatile. Examples of a secondary storage device are Inter
nal Hard drive, external Hard Drive, Flash Disk, CD/DVD, Floppy disk, Memory card.

26. Tertiary Storage
Tertiary storage or tertiary memory provides a third level of storage. Typically it involves a
robotic mechanism which will mount (insert) and dismount removable mass storage media
into a storage device according to the system's demands; this data is often copied to seco
ndary storage before use. [Removable Disks]

27. Connectivity devices
The majority of external peripheral devices connect to the back of the computer‘s system u
nit with cables and connectors. The computer‘s system unit has a variety of ports available
for use by different peripheral device cables. A port is a socket that is used to connect the c
ables from peripheral devices to the computer or the position to plug peripheral devices.
Ports
A port is an interface on a computer through which the device is communicate (send and re
ceive data). Personal computers have various types of ports. Personal computers have por
ts for connecting Monitor/display, printer, mouse, keyboard, scanner, Removable disks and
other peripheral devices. The types of ports are:-

28. USB port
Mic port
Speaker port
CD-ROM
Open & Close button
For CD-ROM
Power ON/OFF
button
Power cable
Inserting port
Voltage Selecting
Button 110V | 230V
Speaker port
USB port
NIC port
VGA port
Parallel port
Serial port
Mic port
Floppy disk
drive

29. ➢ Serial ports: is the oldest technology that is used to connect some types of mouse, keyboard, a
nd other peripherals. As the name indicates, this port sends data serially that is one bit at a tim
e. A serial port is also called male port since it consists of protruding pins. Its transfer rate is close
to 10KBs data.
➢ Parallel Ports: are used primarily for connecting printers to your system. Because of this it is
called LPT (line print) port. It is also called female port since it consists of holes. Parallel ports gen
erate speeds of 100KBs and reflect transfers 10 times faster than serial speeds.
➢ USB (Universal Serial Bus): USB is a high performance-networking standard based on serial
bus architecture. Most new computers and associated peripheral devices like printers and scanner
s support USB. USB ports are used to connect just about any type of peripheral devices speed en
hancements have greatly improved performance with USB 1.0 generating speeds at 14 MB/s and
USB 2.0 attaining speeds of 480MB/s.
➢ Video Graphics Array (VGA) connector is a three-row 15-pin DE-15 connector. The 15-pin V
GA connector is found on many video cards, computer monitors, and some television sets. On lap
top computers or other small devices, a mini-VGA port is sometimes used in place of the full-sized
VGA connector.

30. o Serial port - a 9-pin port. Often called Com ports - Com1, Com2 etc.
Mice and external modems were connected to these ports. They are turqu
oise in colour.
o Parallel port - a 25-pin port used to connect printers, scanners, external har
d disks, zip drives etc. to the computer. Burgundy in colour, they are often called
LPT ports - LPT1, LPT2 etc.
USB to RS232

31. o Video port - used to connect a monitor to the computer system. There are three types:
✓ VGA (Video Graphics Array) port - This is a 15-pin port and is blue in colour. It
is an analogue port and is being replaced by the DVI port.
✓ DVI (Digital Video Interface) port - white in colour, it is a digital port. This me
ans that no conversion is necessary between the computer and the monitor and that me
ans that images can be produced more quickly on the monitor

32. o HDMI (High Definition Multimedia Interface): is a
proprietary audio/video interface or transmitting uncompres
sed video data and compressed or uncompressed digital a
udio data from an HDMI-compliant source.
o Pin type: A,C & D [19], Type B (29).
o RCA (Radio Corporation of America): is a type of el
ectrical connector commonly used to carry audio video and
signals. The name RCA drives from the company Radio Co
rporation of America, which introduced the design in the 1
930s. The connector male plug and female jack are called
RCA plug and RCA jack.
HDMI Cable
RCA Cable

33. o PS/2 port - used to connect keyboards and mice to the computer. The keyboard port
is purple and the mouse port is green.
o Ethernet (NIC )port - used to connect a modem to a telephone line. RJ-45 and
RJ-11 is the technical term for the port.
RJ-11 RJ-45

34. o USB (Universal Serial Bus) port - intended to replace Serial, Parallel and PS/2 ports with
a single standard. 127 devices can be connected to a single USB port. Hot swappable - de
vices can be connected and disconnected while the computer is on there are different USB
standards in use:

35. NIC Port/Network Interface Card
Alternatively referred to as an Ethernet port, the LAN port is a port connection that
allows a computer to connect to a network using a wired connection. In the picture
to the right, is a close up example of what a LAN port looks like for a network cable
using an RJ-45 connector. In the case of this example, the two led lights will blink
when that port is active and receiving activity.

36. Power Supply
A computer power supply has a number of functions:
o Converts Alternating current (AC) to Direct current (DC).
o Transforms main voltage (240 Volts) to the voltages required by the computer.
The main voltages are:
✓ 12 volts for the disk drives as they have motors
✓ 3.3 and 5 volts for the circuit boards in the computer

39. Plug & Socket types around the World
If you’ve ever travelled abroad, you likely have a pack of different outlet and plug adaptors to carry with you
on your travels. Without adaptors, we’d be tech-less in an increasingly tech-reliant world.
But why isn’t there a universal outlet? And what countries use which plugs?
▪ Today, there are 15 different styles of outlets and plugs commonly used around the world. The style of p
lug and outlet that we use in the United States is known as ‘Type A.’ This plug style was invented in 1904
by the American inventor Harvey Hubbell II. Since then, little has changed about the design.
▪ Type A plugs feature two polarised prongs, slightly differing in size. This plug style is considered more dan
gerous and has been outlawed for use in new construction in the United States since 1965.
But why don’t other countries use the same plug style?
▪ Put simply, type A and B plugs and outlets are considered very unsafe by international standards. Plugs ar
en’t insulated, and since wall outlets aren’t recessed, the risk of electrocution or shock is much higher.
There are currently 15 types of domestic electrical outlet plugs in use worldwide, each of which has been assi
gned a letter by the US Department of Commerce International Trade Administration (ITA), starting with A and
moving through the alphabet. These letters are completely arbitrary: they don’t actually mandate anything.

40. Type A
▪ Mainly used in the USA, Canada,
Mexico & Japan.
▪ 2 pins
▪ Not grounded.
▪ 15 A.
▪ Almost always 100 – 127 V.
▪ Socket compatible with plug Type A
Type B
▪ Mainly used in the USA, Canada &
Mexico.
▪ 3 pins, Grounded.
▪ 15 A.
▪ Almost always 100 – 127 V.
▪ Socket compatible with plug Types
A & B
Type C
▪ Commonly used in Europe, South
America & Asia.
▪ 2 pins
▪ Not grounded.
▪ 2.5 A, 10 A & 16 A.
▪ Almost always 220 – 240 V.
▪ Socket compatible with plug Type C

41. Type D
▪ Mainly used in India.
▪ 3 pins, Grounded.
▪ 6 A.
▪ 220 – 240 V.
▪ Socket compatible with plug Type D
(partial and unsafe compatibility
with C, E & F)
Type E
▪ Primarily used in France, Belgium,
Poland, Slovakia & Czechia.
▪ 2 pins, Grounded.
▪ 16 A
▪ 220 – 240 V.
▪ Socket compatible with plug Types
C, E & F
Type F
▪ Used almost everywhere in Europe &
Russia, except for the UK & Ireland.
▪ 2 pins, Grounded.
▪ 16 A
▪ 220 – 240 V
▪ Socket compatible with plug Types C,
E & F

42. Type G
▪ Mainly used in the United Kingdom,
Ireland, Malta, Malaysia, Singapore
& the Arabian Peninsula.
▪ 3 pins
▪ Grounded
▪ Socket compatible with plug Type G
Type H
▪ Used exclusively in Israel, the West
Bank & the Gaza Strip.
▪ 3 pins, Grounded.
▪ Socket compatible with plug Types C
& H (partial and unsafe
compatibility with E & F)
Type I
▪ Mainly used in Australia, New Zealand,
China & Argentina.
▪ 10 A
▪ 220 – 240 V
▪ Socket compatible with plug Type I

43. Type J
▪ Used almost exclusively in Switzerland &
Liechtenstein.
▪ 3 pins, Grounded
▪ 10 A
▪ 220 – 240 V
▪ Socket compatible with plug types C & J
Type K
▪ Used almost exclusively in Denmark &
Greenland.
▪ 3 pins, Grounded.
▪ 16 A 220 – 240 V
▪ Socket compatible with plug types C & K
(partial and unsafe compatibility with E & F)
Type L
▪ Used almost exclusively in Italy & Chile
▪ 3 pins, Grounded
▪ 10 A & 16 A, 220 – 240 V
▪ 10 A socket compatible with plug types
C & L (10 A version) 16 A socket com
patible with plug type L (16 A version)

44. Type M
▪ Mainly used in South Africa.
▪ 3 pins, Grounded
▪ 16 A
▪ 220 – 240 V
Type N
▪ Used in Brazil and South Africa
▪ 3 pins
▪ Grounded
▪ 10 A, 16 A & 20 A
Type O
▪ Used exclusively in Thailand
▪ 3 pins
▪ Grounded
▪ 16 A

45. Device Drivers
Is a particular form of software application that allows one hardware device (such as a person
al computer) to interact with another hardware device (such as a printer).
A device driver may also be called a software driver. - Is a software program that allows the
hardware device to talk to the operating system and create an interface between users and
devices.
Hardware Requirement
The hardware requirements are the requirements of a hardware device. Most hardware only h
as operating system requirements or compatibility.
✓ Processor: is the driver of the computer. Processors are usually differentiated by speed,
measured in gigahertz (GHz). The higher the GHz, the faster the computer will run.
✓ Memory: is used by the processor to run programs. Generally, the more random access m
emory (RAM) you have, the better your computer will run when using several programs at
once.

46. ✓ Hard disk: is used to store the data you create in your business, as well as the progra
ms you use. Its capacity is much greater than the RAM.
if you intend to use a single desktop PC as the main storage location for all your busin
ess data, you will need at least 500 GB.
✓ DVD-R/RW or CD-R/RW: drives can be used to supplement your computer.
Software requirements
Software Requirements deal with defining software resource requirements and pre-requisi
tes that need to be installed on a computer to provide optimal functioning of an application
.
✓ Platform In computing, a platform describes some sort of framework, either in hardwa
re or software, which allows software to run. Typical platforms include a computer's arc
hitecture, operating system, or programming languages and their run time libraries.
✓ Web browser Most web applications and software depending heavily on Internet tech
nologies make use of the default browser installed on system.

47. Other pre-requisite requirements
Some software also has other requirements for proper performance. Internet connect
ion (type and speed) and resolution of the display screen are notable examples.
After you have determine your organization needs, you can now start documenting y
our hardware needs, to help you decide on the specifications, canvassing would be a
great idea.
One by one you can list down the hardware specs for your client.
❑ Processor
❑ RAM or Memory
❑ Hard Disk size
❑ Video Card
❑ LAN Card
❑ DVD drive
❑ Sound Card

48. Entering Peripherals into Equipment Inventory
Hardware inventories
The purpose of a hardware inventory (or registry) is to keep detailed information about all the hardware equipment within a
n organization. Every piece of hardware, including each computer and peripheral device, should be recorded on the invent
ory. Details that should be included within a hardware inventory includes:-
1) Description of hardware device
2) Manufacturer
3) Supplier
4) Model number
5) Serial number
6) Warranty or maintenance conditions
7) Components
8) Location
9) Number and identity of authorised users
10) Purchase price
11) Date of purchase.

49. Documenting peripherals used with each computer
Individual computer inventories will often contain detailed information about the computer‘
s related hardware and software.
Details of computer specification for Inventories

50. Connecting
Workstation to
Internet
To connect computers to the inter
net connection for accessing
information over a network either
by using connection based or
connectionless internet
infrastructure the user must be co
nnected to the internet access
through internet service provide
rs (ISP).
Dialup Connection
Dial-up internet access is a form
of Internet access that uses the
facilities of the public switched
telephone network (PSTN) to
establish a dialled connection to
an Internet service provider ISP
via telephone lines.
ADSL Connection
ADSL (Asymmetric Digital
Subscriber Line or DSL for short)
is a high-speed Internet access
service that utilizes existing
copper telephones lines to send
and receive data at speeds that
far exceed conventional dial-up
modems.

51. Digital Subscriber Line (DSL)
An "always-on" technology; there is no need to dial up each time to connect to the Internet. -
Uses the existing copper telephone lines to provide high-speed data
communication between end users and telephone companies.
Cable Connection
In telecommunications, cable Internet access, often called simply cable Internet, is a form of
broadband Internet access that uses the cable television infrastructure.
Cable connection has the following characteristics. It uses a separate cable than phone line
to transfer data, Very fast and reliable, Fixed monthly fee.

52. Advantage of cable connection
o Very fast
o Always on
o Doesn‘t affect to make/receive a phone call, since it uses a separate cable
Disadvantages of cable connection
o Doesn‘t available everywhere
o It needs a special modem called cable modem
Wireless connection (Wi-Fi network Connection)
❑ Wi-Fi is the wireless technology used to connect computers, tablets, smartphon
es and other devices to the internet.
❑ Wi-Fi is the radio signal sent from a wireless router to a nearby device, which
translates the signal into data you can see and use.

53. Thank you
Connecting Hardware Peripherals
www.gemechisbido.com