Introduction to
Computers
An electronic, programmable device that:
 Accepts
data in the form of Input
 Manipulates
 Produces
that data by Processing
results in the form of Output
 Stores
for future use through Storage
devices
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2
Four basic operations:
1.
2.
3.
4.
Input
Processing
Output
Storage
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3
Computers perform operations comprising
the information processing cycle to
manipulate data into information and
store for future use.

Data is a collection of facts, or
unprocessed items.

Information is the portion of those
facts that conveys meaning and is useful
to the user.
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4
 Hardware-the
physical components that make
up a computer system. Six primary components
include:
Input Devices
Output Devices
Processor
Storage devices
Memory
Communication
 Software-detailed
set of instructions that tells
a computer exactly what to do. {aka Computer
Program}

Booting is the process that loads the operating
system into RAM (Random Access Memory).
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5
Allow you to enter data, programs, commands, and user
responses into a computer.

Keyboard-contains keys you press to enter data.

Mouse-pointing device that controls the pointer.

Microphone-a device that converts sound waves into
electrical energy to be broadcast, recorded or
amplified.

Scanner-light-sensing device that reads printed text
and graphics and translates the results into digital
form.

Digital Camera-records photographic images,
sound and/or video in digital form.
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
Graphics/Digitizing Tablet-uses a stylus to sketch
drawings or images on surface.

Stylus-resembling a pen, uses pressure to input
data.

Touchpad-controls pointer movements by sliding
your fingertip on the pad.

Touch Screens –LCD display capable of sensing
multiple points of contact.

Game Controllers-consist of game pads, joysticks,
gloves, steering wheels, trackballs, etc.
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Case that contains electronic components of the
computer used to process data. The Motherboard
is the main circuit board and includes the processor,
memory and expansion slots.
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 Processor,
aka Central Processing Unit
(CPU)-is the brain of the computer that
interprets and executes the instructions that
operate a computer.
Control Unit-interprets the instructions
 Arithmetic/Logic Unit-performs the logical and
arithmetic processes.

 Memory,
aka Random Access Memory(RAM)consists of the electronic components that
temporarily store instructions waiting to be
executed by the processor.
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The amount of memory in computers is
measured in bytes.
 Terabyte
(TB)- one trillion memory locations
 Gigabyte
(GB)-one billion memory locations
 Megabyte
 Kilobyte
 Byte-one
(MB)-one million memory locations
(K)-one thousand memory locations
memory location
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Make information resulting from processing
available for use.
 Printers-produce
a hard copy also called a
printout and classified as either Impact or
Nonimpact.
 Monitors-produce
a soft copy that visually
conveys text, graphics, and video information.
 Speakers-converts
electrical signals into sounds
loud enough to be heard at a distance.
 Projectors-an
optical instrument that projects
an enlarged image onto a screen.
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 Impact
Printers-print by striking an inked
ribbon against the paper.
 Dot-Matrix
Printer-produces printed images
when tiny pins strike
an inked ribbon on
continuous form paper.
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 Nonimpact
Printers-form characters by means
other than striking a ribbon against paper.
 Ink-jet
Printers (DeskJet or Photo
Printers)-produce images by using a
nozzle that sprays tiny drops of ink
onto a page.
 Laser
Printers-high-speed,
highest- quality printers that form
images to be printed from a beam of
light focused on a photoconductor
drum similar to a copying machine.
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Monitors are composed of individual picture
elements called Pixels that form parts of a
character or graphic shape on the screen.
Panel Monitors-take up much less desk
space.
 Liquid Crystal Display (LCD)-Monitors use a
 Flat
liquid display crystal, similar to a digital watch,
to produce images on the screen.
Ray Tube (CRT)-display graphics
through technology used in most televisions.
 Cathode
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Used to store instructions, data, and
information when they are not being used in
memory.
 Four
basic types of storage media include:
 Magnetic Disks
 Optical Discs
 Tape
 Miniature Mobile Storage Media
Slide 15
Use magnetic particles to store items such as data,
instructions, and information on a disk’s surface.
 Hard
Disk-contains one or
more inflexible, circular
platters that magnetically
store data, instructions, and
information.
 Floppy
Disks (Diskette)inexpensive portable storage
medium.

3.5” only stores 1.44 MB
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Process of preparing a disk to be read from or
written on by dividing the disk into tracks and
sectors.
narrow recording
band that forms a full
circle on the surface of a
disk.
 Track-a
 Sector-pie-shaped
storage
section, which breaks the
tracks into small arcs
storing up to 512 bytes of
data.
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Flat, round, portable storage medium that
reads and records data using laser technology.
 CD-ROM
& DVD-ROM (Read-Only Memory)-can
read but not write on (record) or erase.
 CD-R
& DVD-R (Recordable)-record on each part
only one time but cannot erase.
 CD-RW
& DVD-RW (Rewritable)-erasable optical
discs you can write on multiple times.
DVDs (Digital Versatile Discs) are the highest
capacity optical discs capable of storing 4.7-17 GB.
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Optical Disc
CD-ROM
CD-R
CD-RW
DVD-ROM
DVD-R
DVD-RW
Read






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Write Erase






Magnetically coated ribbon of plastic housed in a
tape cartridge capable of storing large amounts
of data at a low cost. Primarily used for longterm storage and Backup.
A
Backup is a duplicate
of a file, program, or
disk that you can use in
case the original is lost,
damaged, or destroyed.
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Flash Memory Cards-solid-state media
that consist entirely of electronics and contain
no moving parts.
USB Flash Drive-flash memory storage
device that plugs into a USB port on a
computer or mobile device.
Smart Card-stores data on a thin
microprocessor embedded in the card.
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