Hardware

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Hardware
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Types of computers - 1
MINI COMPUTER Very powerful, used for specialist
tasks, or uses.
MAINFRAME Used by large companies. These will
take up a whole room, and may not need people in
the room.
STAND ALONE DESKTOP PC HOME COMPUTER
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Types of computers - 2
LAPTOP Just as powerful as as PC but can run on
batteries (for 3 to 4 hours only).
PALMTOP Very small, but less powerful, computers.
Can be carried in a pocket anywhere.
STAND ALONE DESKTOP PC HOME COMPUTER
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Types of computers - 3
WAN (Wide Area Network) These computers are
connected together across buildings, counties or
even countries. The Internet is the biggest WAN.
LAN (Local Area Network) A number of computers
connected to a server which holds all the
software. Usually in one building/room.
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Input devices - 1

• KEYBOARD
• Typing information into any software
• Word processor
• DTP

TOUCH SENSITIVE SCREEN To select options from the
screen by touch. Or for the physically disabled
who cannot use a mouse.
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Input devices - 2
GRAPHICS TABLET to enable you to draw freehand
into the computer
MOUSE To selects menu options or to draw
with
MICROPHONE To enable you to talk directly into
a word processor (good for the dyslexic or the
disabled to use).
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Input devices - 3
BAR CODE SCANNER To scan in bar codes in
supermarkets, or other shops. This version is
hand held.
MAGNETIC STRIP(E) READER These are usually built
into POS tills at shops and supermarket to make
payments using cards.
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Input devices - 4
SCANNER To copy photographs,
pictures, text from books / magazines, into the
computer.
DIGITAL CAMERA To take photographs which
can be fed directly into the computer
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Input devices - 5
OMR READER This will read marks on a page. Used
for school registers and multiple choice tests.
MICR READER The ink is magnetised before
reading. Very reliable so used on cheques.
OCR READER This reads normal text. Most home
scanners can do this
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Output devices 1
LASER PRINTER For fast high quality output.
MONITOR, VDU To allow you to see what is
happening, or what you have typed.
COLOUR PRINTER For slower prints in full
colour.
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Output devices - 2
SPEAKERS To listen to music, language, or
commentary.
DATA PROJECTOR To show what is on the monitor
screen to large audiences.
HEADPHONES Just like speakers but the noise does
not distract others in the same room.
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Output devices -3
PLOTTER For producing technical drawings and maps
CUTTER For cutting out designs in steel, plastic
or wood.
MILLING MACHINE To cut out shapes and holes using
a drill (as in room 24).
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Output devices - 4

• MOTORS can be used as output devices in computer
  control. Examples are
• Washing machines
• Burglar alarms

• LIGHTS can be used as output devices in computer
  control. Examples are
• Disco lights
• Burglar alarms

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Storage devices - 1
CDROM DRIVE (DVD) used to store medium amounts of
data
FLOPPY DISK DRIVE used to store small amounts of
data
ZIP DRIVE used to store medium amounts of data
HARD DRIVE used to store large amounts of data
(fixed).
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Storage devices - 2
ON-LINE STORAGE Free 30Mb with Yahoo just click
on Briefcase. Access your files from anywhere
in the world.
PAPER Paper is not a device, but counts as one
method of permanently storing data.
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Communication devices - 1
MODEM converts or changes digital signals into
analogue signals
DIGITAL computer signals
ANALOGUE phone line signals
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Communication devices - 2

• How to send a FAX
• Put in letter
• Dial FAX number
• Wait for the beeps
• Press SEND

Used for sending letters, documents or pictures
instantaneously to a second FAX. Internet is not
needed, just a phone line.
FAX MACHINE
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Hardware Summary

• Output devices
• Receive information from the computer

• Input devices
• Send information into the computer

• Comms devices
• Modems convert digital signals into analogue
  signals
• And visa versa

• Storage devices
• Keep information for use later
• You output to it and input from it

• Types of computers
• Main/mini/micro
• Laptop/palmtop