1. C. Demetriou (2009) 1 October 2009 1
žHardware:
› Physical equipment that makes up a computer
system.
› If you can kick it or take an axe to it, it is hardware.
žSoftware:
› Programs, routines and procedures (together with
their associated documentation) which can be run
on a computer system.
It is important not to confuse the media used to
transport software with software itself!
› A CD is a piece of hardware which you can touch
and kick and it may contain software which you
cannot touch. The CD is not software!
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2. Examples of Hardware
ž Central Processor (CPU)
ž Peripherals – these are hardware
devices which are attached to the
central processor.
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They can be classified into 4
types:
ž Input:
› Keyboard, Mouse, Scanner
ž Output:
› Monitor, Speakers
ž Backing Storage:
› Hard Disk, Flash Drive
ž Communications:
› Modem
3. ž Standardisation is the imposition, by a
third party, or with agreement, of a set of
standards on manufacturers.
› W3C : the world wide web Consortium
› ISO : International Standards Organisation
ž ICT suffers from a lack of standardisation
for both Hardware & Software.
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ž Lack of standardisation has the following
disadvantages
› Cost
› Availability
› Technical Support
ž Software
› Word Processors should all use the same file format
but do they?
› Do all web browsers display web pages in exactly
the same way?
ž Hardware
› Do all PCs accept the same hardware upgrades?
› When buying a game for a PC what must you
consider?
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4. ž Takeovers
› When a company gets taken over there is
likely to be incompatibility between their
own systems. This may be down to the two
companies having separate standards.
› This leads to:-
– No communication between systems
– Miscommunication between systems
(incorrect data being shared)
– New equipment having to be purchased
– Staff training
– Lack of tech support on new systems
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ž An input device is a piece of Hardware
that gets data from outside the
computer system into the computer
system
› Keyboard
› Mouse
› Scanner
› Graphics Tablet
› Digitiser
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5. ž Output devices are used to display the
result of processing to the user. They are
used to get data from inside the
computer to outside.
› Monitor (LCD, CRT)
› Printer
› Plotter
› Loud Speakers
› LEDs
› Buzzer
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Loud Speaker
ž Used to give confirmation of actions
ž Can be used to read lines of text
ž Increased use with CDs and Music
(MP3s)
ž Music technology requires specialist
sound output devices.
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6. LED and Buzzer
ž LED
› Can display the status of a device
– HDD light displayed when in use
– Lights on a Printer indicates status
– Can be used to signal to hearing impaired
people
ž Buzzers
› Gives confirmatory actions
– Set sounds to events in Windows
– Bar Codes beep to indicate successful entry
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Monitor (VDU)
ž Most common Output device
ž Range of Sizes – standard is 17”, but 19”
or 21” available for specialists,
› For example, designers
› Newspapers and magazines
ž High quality output
ž Possible health issues
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7. ž Three main types of printers:
› Impact/Dot matrix Printers
› InkJet Printers
› Laser Printers
ž Choice of:
› Colour
› Black and White
ž Selection of different
resolutions.
› DPI [Dots per Inch]
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ž Physical Connection between print head
and paper
ž Noisy
ž Slow
ž Cheap to run
ž Colour or Black and White
ž Low Resolution
ž Can do Carbon Copies
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8. ž Ink is fired at the page and the number
of DPI can be very high
› High resolution
ž Colour or B&W
ž High Running Costs
ž Faster than a Dot Matrix but not as fast
as laser
ž Cannot print Carbon Copies
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ž High Quality Images
ž Fast Printing
ž Colour or Black and
White
(Colour is expensive)
ž Medium to low running costs
ž Excellent Quality
ž Can produce OHTs
ž Cannot do Carbon Copies
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9. ž Storage devices are used to hold data
and programs.
ž They are non-volatile.
› Floppy Disks [now obsolete]
› Hard Disks [SSD’s on the horizon]
› Optical Disks (CD, DVD, Blu-ray)
› Tape Drives
› Flash Memory (MMC, SD, CF, xD, MS)
ž Sometimes referred to as mass storage.
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ž Motor Impairment is the loss or limitation
in muscle control or movement, or a
limitation in mobility.
› Mouth stick
› Puff-Suck Switch
› Tongue-activated joystick
› Eye-typer
› Foot mouse
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10. ž Specialist software can help people with
disability
› Text to speech
› Speech to text
› Auditory feedback (windows sounds)
› Screen magnifier
› Predictive text
› Sticky Keys
ž Which are available in a standard install
of Windows?
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ž Operating Systems
Hardware
ž User Interfaces
ž Utilities Operating System
ž Applications
Applications
Utilities
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11. ž A program or suite of programs that control
the entire operation of the computer.
ž Deals with the basic functions of the
computer.
ž At a technical level, it handles the basic
and central functions such as input and
output operations and interrupts.
ž Examples include: MS-DOS, Win 2000, Win
XP, UNIX, Linux, FreeBSD, Symbian, MacOS
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User Interfaces
ž These are pieces of software which fit
onto existing packages to alter the user
interface.
ž More commonly, they are now referred
to as “Skins”
ž They allow for individual customisation of
the user interface
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12. ž Command-Based The user
ž Forms interface is the
method by
ž Menus which
the user
ž Natural Language communicates
with the
computer.
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ž Command Prompt
ž Commands are typed
ž Each command can have switches
› These are different modes in which the
command can be run.
ž Expert users only
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13. ž Data Labels giving assistance
ž Boxes to enter/choose data
ž Used for Data entry (records)
ž Making choices is easier
ž The user is given choices
ž Useful for novice users
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ž Series of related
items which can
be clicked
ž Presents a
limited choice
ž Novice-friendly
ž Structured into
options
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14. ž User types or speaks in normal
everyday language and the
computer responds
ž Used in Microsoft Help and Ask
Jeeves Web Site
ž Useful for novice users as they do
not need to understand the
computer to use it.
ž With vocal input, useful for
physically handicapped people.
ž Hand writing recognition on PDAs
and Nintendo DS
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ž GUI (Graphical User Interface)
› This is an interface that is based on graphics
and pictures rather than text.
ž WIMP (Windows, Icons, Mouse, Pointer)
› This is a particular type of GUI.
ALL WIMPs are GUIs, but not all GUIs are
WIMPs
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15. ž Designed to perform a commonplace task,
for example the transfer of data from one
storage device to another, sorting a set of
data, disk editor.
ž They are designed to make the operation
of the computer easier.
› Windows Explorer
› Defrag
› Anti-Virus
› Anti-Spyware
› Burning CDs/DVDs
› File Compression
› Printer monitoring
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ž Generic
ž Tailor-Made
ž Off-the-shelf
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16. ž These are off-the-shelf packages which
do not meet a specific purpose but
serve a general purpose
ž For example:
› Microsoft Office and components
› Corel Suite
› Adobe CS suite
› Lotus Suite
– Word Processors, Spreadsheets, Databases
ž The software can then be customised to
produce the result you want.
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ž Either:
› Bespoke
– The application is written for the purpose by a
software house
– Disadvantages: Time consuming, expensive, limited
support/books.
– Advantages: Fulfils purpose, individual support
ž Or:
› Customisation
– A generic application is customised using a
programming language
– Disadvantages: Need to purchase the application and
you get more than required.
– Advantages: Cheaper, lots of support.
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17. ž Purchasing solutions from a shop without
alteration
ž For example:
› SAGE payroll package
› Heritage Library Database
ž The idea is to be able to open the
package and run the software which
delivers a specific solution.
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