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LYCEUM OF THE PHILIPPINES. – DAVAO
Km. 11, C.P. Garcia Highway, Buhangin District, Davao City
LIVING IN THE ERA: HISTORY OF COMPUTER
Lesson I. Computer: Definition, Types, Characteristics, Components
I.
What is a computer?
a. Computer is a programmable machine.
b. Computer is an electronic device that manipulates information, or data. It
has the ability to store, retrieve, and process data.
c. Computer is a machine that manipulates data according to a list of
instructions (program).
d. Computer is any device which aids humans in performing various kinds
of computations or calculations.
II.
Three principal characteristics of computer:
a. It responds to a specific set of instructions in a well-defined manner.
b. It can execute a pre-recorded list of instructions.
c. It can quickly store and retrieve large amounts of data.
III.
Components of a Computer
a. Input devices
These are devices that send data to a computer and allow you to
interact and control it.
•
Keyboard – one of the primary input devices used to input data
and commands. It has function keys, control keys, arrow keys,
keypad and the keyboard itself with the letters, numbers and
commands. Keyboards are connected to the computer through USB
or Bluetooth. A laptop keyboard is more compact than a desktop
keyboard to make the laptop smaller and lighter. Smartphones and
tablets use on-screen keyboard to input messages and select
commands.
•
Mouse is the most popular pointing device. It is a very famous
cursor-control device having a small palm size box with a round ball
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LYCEUM OF THE PHILIPPINES. – DAVAO
Km. 11, C.P. Garcia Highway, Buhangin District, Davao City
at its base, which senses the movement of the mouse and sends
corresponding signals to the CPU when the mouse buttons are
pressed.
•
A trackball is a pointing device consisting of a ball held by a
socket containing sensors to detect a rotation of the ball about two
axes—like an upside-down mouse with an exposed protruding ball.
•
A touchpad also called a trackpad is a touch-sensitive pad that
lets the user move the pointer by touching or dragging his or her
finger on the pad. Touchpads are commonly built-in on laptops and
computers.
•
Microphone – an input device that allows users to input audio
into their computers.
•
Scanner – is an input device that reads an image and converts
it into a digital file. A scanner is connected to a computer through
USB. There are different types of scanners:
•
Flatbed scanner – uses a flat surface to scan documents
•
Handheld scanner – the scanner is dragged over the page to be
scanned
•
Digital Camera – is an input device that takes pictures digitally.
Images are stored as data on memory cards. It has an LCD screen
that allows users to preview and review images.
•
Webcam – is an input device connected to the computer and
the internet that captures still picture or motion video.
•
Stylus – is a pen-shaped input device used to write or draw on
the screen of a graphic tablet or device.
b. Output devices
These are hardware components that transmit information to one or
more people.
•
Printer – produces text and graphics on a physical medium
such as paper. There are two types of printer. The impact and nonimpact printer. An impact printer makes contact with the paper by
pressing an inked ribbon against the paper using a hammer or pins,
e.g. dot-matrix printer. A non-impact printer does not use a striking
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LYCEUM OF THE PHILIPPINES. – DAVAO
Km. 11, C.P. Garcia Highway, Buhangin District, Davao City
device to produce characters on the paper, and because it does not
hammer against the paper, the printer produces less noise, e.g.
inkjet printers and laser printers.
•
Monitor – displays texts, graphics, and videos on a screen.
CATHODE RAY TUBE (CRT) – is a vacuum tube containing an
electron gun at one end and a fluorescent screen at the other end.
From this electron gun, a process called thermionic emission
generates a strong beam of electrons. These electrons travel through
a narrow path within the tube with high speed using various
electromagnetic devices and finally strike the phosphor points
present on the fluorescent screen, thus creating an image.
LIQUID CRYSTAL DISPLAY(LCD) – is a flat – panel display that
consists of a layer of color or monochrome pixels arranged
schematically between a couple of transparent electrodes and two
polarizing filters. Optical effect is achieved by polarizing the light in
varied amounts and making it pass through the liquid crystal layer.
LIGHT EMITING DIODE (LED) – is a flat – panel display that
uses light – emitting diodes for backlighting. The display is of LCD
only but the backlighting is done by LEDs. LED monitors are said to
use much lesser power than CRT and LCD. Thus, they are considered
environment- friendly.
•
SPEAKERS allow you to hear audio such as music, voice, and
other sounds. The signal used to produce the sound that comes from
a computer speaker is created by the computer’s sound card.
•
Storage devices - A computer can be utilized with only
processing, memory, input and output devices. To make it very
valuable, however, a computer also needs a place to hold program
files and all related files when they are not in use. The goal of using a
storage is to keep data permanently.
Flash disk drive – a small portable storage device.
Hard disk drive – most PCs have at least one non-removable hard
disk that is regarded as a non-volatile memory which permanently
stores and retrieves data.
Compact disc – flat, round, and portable metal disc. One type of
compact disc is the CD-ROM, which can be accessed using most CD
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LYCEUM OF THE PHILIPPINES. – DAVAO
Km. 11, C.P. Garcia Highway, Buhangin District, Davao City
and DVD drives. Another type of compact disc is a DVD-ROM, which
has enough storage capacity to store a full-length movie.
IV.
Types of Computers
Desktop computers – are computers designed to be placed on a
desk, and are normally made up of a few different parts, including
the computer case, central processing unit (CPU), monitor, keyboard
and mouse.
Laptop computers – are battery-powered computer devices whose
portability makes them possible to use almost anytime, anywhere.
Tablet computers – are hand-held computers with touch-sensitive
screen for typing and navigation.
Smartphones – are hand-held telephones which can do things that
computers can do, including browsing and searching the internet
and even playing console games.
•
Wearables – include fitness trackers and smartwatches that
can be worn throughout the day.
•
Smart TVs – are the latest television sets that include
applications present in computers, e.g. video streaming from the
internet directly onto the TV and can also be used as a computer
monitor and gaming monitor.
¬ Caoili-Tayuan, R.R. & Eleazar, M.V. (2019).
Living in the Information Technology Era