ASSINGNMENT
CHAPTER 6
Chapter
Review Pages 332 – 333
Discovering
Computer (“Living In the Digital World 2011”)
Lecture : Mr.
Tri Djoko Wahjono
Student
: Williem
[1701309721]
1. What are the four types of output?
Output is data that has been processed into a
useful form That is, computers process data (input) into information (output).
The form of output varies, depending on the hardware and software being used
and the requirements of the user. Monitors, traditional notebook computers,
netbooks, Tablet PCs, portable media players, smart phones, digital cameras,
and other mobile devices have screens that allow users to view documents, Web
sites, e-mail messages, photos, videos, and movies. Many printers enable users
to print color documents and photos. Through the computer’s speakers,
headphones, or earbuds, users listen to sounds, music, and voice messages.
While working with a computer, a user encounters
four basic types of output: text, graphics, audio, and video. Very often, a
single form of output, such as a Web page, includes more than one of these
types of output.
·
-Text: examples of output that
primarily contain text are memos, letters, press releases, reports, classified
advertisements, envelopes, mailing labels, and text messages. On the Web, users
view and print many other types of text-based output. These include blogs, news
and magazine articles, books, television show transcripts, stock quotes,
speeches, and lectures.
·
-Graphics: many forms of output include
graphics to enhance visual appeal and convey information. Business letters have
logos. Reports include charts. Newsletters use drawings, clip art, and photos.
Users print high-quality photos taken with a digital camera. Many Web sites use
animated graphics, such as blinking icons, scrolling messages, or simulations.
·
-Audio: Users download their
favorite songs from iTunes and listen to the music while working on the
computer. Software such as games, encyclopedias, and simulations often have
musical accompaniments for entertainment and audio clips, such as narrations
and speeches, to enhance understanding. On the Web, users tune into radio and
television stations and listen to audio clips, podcasts, or live broadcasts of
interviews, talk shows, sporting events, news, music, and concerts. They also use
the Internet to conduct real-time conversations with friends, coworkers, or
family members, just as if they were speaking on the telephone.
·
-Video: as with audio, software and web
sites often include video clips to enhance understanding. Vodcasts and video
blogs, for example, add a video component to the traditional podcast and blog.
Users watch a live or prerecorded news report, view a reply while attending a
live sporting event, observe weather conditions, or enjoy a live performance of
their favorite musician or musical group on a computer or mobile device.
Instead of renting a movie, users can download movie content from a Web site
for a fee and then watch the entire movie on a computer or mobile device.
Attaching a video camera to the computer allows users to watch home movies on
the computer. They also can attach a television’s antenna or cable to the
computer and watch a television program on the computer screen.
2. What are
the characteristics of various display devices?
A display device, or simply display, is an output
device that visually conveys text, graphics, and video information. Information
on a display device, sometimes called soft copy, exists electronically and
appears for a temporary period.
Display devices consist of a screen and the components
that produce the information on the screen. Desktop computers typically use a
monitor as their display device. A monitor is a display device that is packaged
as a separate peripheral. Some monitors have a tile-and-swivel base that allows
users to adjust the angle of the screen to minimize neck strain and reduce
glare from overhead lightning. With some, you can rotate the screen. Adjustable
monitor stands allow you to adjust the height of the monitor. Monitor controls
permit users to adjust the brightness, contrast, positioning, height, and width
of images. Some have integrated speakers and/or a build-in Web cam.
Most mobile computers and devices integrate the
display and other components into the same physical case. Some have touch
screens. Traditional notebook computers and netbooks have a display that
attaches with a hinge to the system unit. Tablet PCs are available with two
types of displays: one that attaches with a hinge and one built into the top of
the case. Some smart phone and digital camera displays also attach with a hinge
to the device. On other smart phones and most PDAs, portable media players,
digital cameras, and handheld game consoles, the display is built into the
case. Newer vehicles integrate a display in the dashboard, enabling drivers to
control audio, video, navigation, temperature, and other settings. Most display
devices show text, graphics, and video information in color. Some, however are
monochrome. Monochrome means the information appears in one color (such as
white, amber, green, black, blue, or gray) on a different color background
(such as black or grayish-white). Some mobile devices use monochrome displays
because they require less battery power.
Two types of display devices are flat-panel
displays and CRT monitors. A flat-panel display is a lightweight display device
with a shallow depth and flat screen that typically uses LCD (liquid crystal
display) or gas plasma technology. Types of flat-panel displays include LCD
monitors, LCD screens, and plasma monitors. All flat-panel displays and some
CRT monitors have a flat screen. The term, flat screen, means the screen is not
curved.
3. What
factors affect the quality of an LCD monitor or LCD screen?
An LCD monitor is a desktop monitor that uses
liquid crystal display to produce images. These monitors produce sharp,
flicker-free images. The quality of an LCD monitor or LCD screen depends
primarily on its resolution, response time, brightness, dot pitch, and contrast
ratio.
·
-Resolution is the number of
horizontal and vertical pixels in a display device. For example, a monitor that
has 1440 x 900 resolution displays up to 1440 pixels per horizontal row and 900
pixels per vertical row, for a total of 1,296,000 pixels to create a screen
image. Recall that a pixel (short for picture element) is a single point in an
electronic image. A higher resolution uses a great number of pixels and thus
provides a smoother, sharper, and clearer image. As you increase the
resolution, however, some items on the screen appear smaller. With LCD monitors
and screens, resolution generally is proportional to the size of the device.
For example, a widescreen 19-inch LCD monitor typically has a resolution of
1440 x 900, while a widescreen 22-inch LCD monitor has a resolution of 1680 x
1050. LCDs are geared for a specific resolution, called the native resolution.
Although you can change the resolution to any setting, for optimal results, use
the monitor’s native resolution setting.
·
-Response time of an LCD monitor or
screen is the time in milliseconds (ms) that it takes to turn a pixel on or
off. LCD monitors’ and screens’ response times range from 3 to 16 ms. The lower
the number, the faster the response time.
·
-Brightness of an LCD monitor or LCD
screen is measured in nits. A nit is a unit of visible light intensity equal to
one candela (formerly called candlepower) per square meter. The candela is the
standard unit of luminous intensity. LCD monitors and screens today range from
250 to 550 nits. The higher the nits, the brighter the images.
·
-Dot pitch, sometimes called pixel
pitch, is the distance in millimeters between pixels on a display device. Text
created with a smaller dot pitch is easier to read. Advertisements normally
specify a monitor’s dot pitch or pixel pitch. Average dot pitch on LCD monitors
and screens should .30 mm or lower. The lower the number, the sharper the
image.
·
Contrast ratio describes the difference
in light intensity between the brightest white and darkest black that can be
displayed on an LCD monitor. Contrast ratios today range from 500:1 to 2000:1.
Higher contrast ratios represent color better.
4. What are
various ways to print?
Until a few years ago, printing a document
required connecting a computer to a printer with a cable. Although many users
today continue to print using this method, a variety of printing options are
available.
Today, wireless printing technology makes the task
of printing from a notebook computer, smart phone, or digital camera much
easier. Two wireless technologies for printing are Bluetooth and infrared. With
Bluetooth printing, a computer or other device transmits output to a printer
via radio waves. The computer or other device and the printer do not have to be
aligned with each other; rather, they need to be within an approximate 30-foot
range. With infrared printing, a printer communicates with a computer or other
device using infrared light waves. To print from a smart phone, for example, a
user lines up the IrDA port on the smart phone with the IrDA port on the
printer.
Instead of downloading photos from a digital
camera to a computer, users can print these digital photos using a variety of
techniques. Some cameras connect directly to a printer via a cable. Others
store photos on memory cards that can be removed and inserted in the printer.
Some printers have a docking station, into which the user inserts the camera to
print photos stored in the camera.
Finally, many home and business users print to a
central printer on a network. Their computer may communicate with the network
printer via cables or wirelessly.
5. How is a
nonimpact printer different from an impact printer?
·
A printer is an output
device
that produces text and graphics on a physical medium such as paper. Printed
information, called hard copy exists physically and is a more permanent form of
output than that presented on a display device (soft copy).
·
A nonimpact printer forms characters and
graphics on a piece of paper without actually striking the paper. Some spray
ink, while others use heat or pressure to create images. Commonly used nonimpact
printers are ink-jet printers, photo printers, laser printers, thermal
printers, mobile printers, label and postage printers, plotters, and
large-format printers.
6. What are
ink-jet printers, photo printers, laser printers, multifunction peripherals,
thermal printers, mobile printers, label and postage printers, and plotters and
large-format printers?
·
Ink-jet printers: An ink-jet printer is a
type of nonimpact printer that forms characters and graphics by spraying tiny
drops of liquid ink onto a piece of paper. Ink-jet printers have become a
popular type of color printer for use in the home. A reasonable quality ink-jet
printer costs less than $100. Ink-jet printers produce text and graphics in
both black-and-white and color on a variety of paper types. These printers
normally use individual sheets of paper stored in one or two removable or
stationary trays. Ink-jet printers accept papers in many sizes, ranging from 3
x 5 inches to 8 ½ x 14 inches. Available paper types include plain paper,
ink-jet paper, photo paper, glossy paper, and banner paper. Most ink-jet
printers can print photographic-quality images on any of these types of paper.
·
-Photo printers: A photo printer is a
color printer that produces photo-lab-quality pictures. Some photo printers
print just one or two sizes of photos, for example, 3 x 5 inches and 4 x 6 inches.
Others print up to letter size, legal size, or even larger. Some even print
panoramic photos. Generally, the more sizes the printer prints, the more
expensive the printer. Many photo printers use ink-jet technology. With models
that can print letter-sized documents, users connect the photo printer to their
computer and use it for all their printing needs. For a few hundred dollars,
this type of photo printer is ideal for the home or small business user. Other
photo printer technologies are discussed later in the chapter. Most photo
printers are PictBridge enabled, so that you can print photos directly from a
digital camera by connecting a cable from the digital camera by connecting a
cable from the digital camera to a USB port on the printer.
·
Laser printers: A laser printer is a
high-speed, high-quality nonimpact printer. Laser printers are available in
both black-and-white and color models. A laser printer for personal computers
ordinarily uses individual 8 ½ x 11-inch sheets of paper stored in one or more
removable trays that slide in the printer case. Some laser printers have
built-in trays that accommodate different sizes of paper, while others require
separate trays for letter-and legal-sized paper. Most laser printers have a
manual feed slot where you can insert individual sheets and envelopes. Laser
printers print text and graphics in high-quality resolutions, usually 1200 dpi
for black-and-white printers and up to 2400 dpi for color printers. While laser
printers usually cost more than ink-jet printers, many models are available at
affordable prices for the home user. Laser printers usually print at faster
speeds than ink-jet printers.
·
Multifunction peripherals: A multifunction
peripheral (MFP), also called an all-in-one device, is a single device that
looks like a printer or a copy machine but provides the functionality of a
printer, scanner, copy machine, and perhaps a fax machine. A fax machine is a
device that codes and encodes documents so that they can be transmitted over
telephone lines. The documents can contain text, drawings or photos, or can be
handwritten. The features of these devices vary. Another advantage of these
devices is they are significantly less expensive than if you purchase each
device separately. If the device breaks down, however, you lose all four
functions, which is the primary disadvantage.
·
Thermal printers: A thermal printer
generates images by pushing electrically heated pins agains heat-sensitive
paper. Basic thermal printers are inexpensive, but the print quality is low and
the images tend to fade over time. Self-service gas pumps often print gas
receipts using a built-in lower-quality thermal printer. Many point-of-sale
terminals in retail and grocery stores also print purchase receipts on thermal
paper. Two special types of thermal printers have high print quality and can
print at much faster rates than ink-jet and laser printers. A thermal
wax-transfer printer generates rich, nonsmearing images by using heat to melt
colored wax onto heat-sensitive paper. Thermal wax-transfer printers are more
expensive than ink-jet printers, but less expensive than many color laser
printers.
·
Mobile printers: a mobile printer is a
small, lightweight, battery-powered printer that allows a mobile user to print
from a notebook computer, smart phone, or other mobile device while traveling.
Barely wider than the paper on which they print, mobile printers fit easily in
a briefcase alongside a notebook computer. Mobile printers mainly use ink-jet,
thermal, thermal wax-transfer, or dye-sublimation technology. Many of these
printers connect to a USB port. Others have a built-in wireless port through
which they communicate with the computer wirelessly.
·
Label printer: a label printer is a
small printer that prints on an adhesive-type material that can be placed on a
variety of items such as envelopes, packages, optical discs, photos, file
folders, and toys. Most label printers also print bar codes. Label printers
typically use thermal technology.
·
Postage printer: A postage printer is a
special type of label printer that prints postage stamps. Some have built-in
digital scales for weighing letters and packages. Postage printers allow users
to buy and print digital postage, often called Internet postage, which means
you purchase an amount of postage from an authorized postal service Web site.
Each time a postage stamp prints, your postage stamp prints, your postage
account is updated. Although you can print Internet postage on an ink-jet or
photo printer, postage printers can be more economical because they use thermal
technology instead of ink catridges.
·
Plotters and large-format
printers:
Plotters are sophisticated printers used to produce high-quality drawings such
as blueprints, maps, and circuit diagrams. These printers are used in
specialized fields such as engineering and drafting and usually are very
costly. Current plotters use a row of charged wires to draw an electrostatic
pattern on specially coated paper and then fuse toner to the pattern. The
printed image consists of a series of very small dots, which provides
high-quality output. Using ink-jet printer technology, but on a much larger
scale, a large-format printer creates photo-realistic-quality color prints.
Graphic artists use these high-cost, high-performance printers for signs, posters,
and other professional quality displays. Plotters and large-format printers can
accommodate paper with widths up to 98 inches because blueprints, maps, signs,
posters and other such blueprints, maps, signs, posters and other such drawings
and displays can be quite large. Some plotters and large-format printers use
individual sheets of paper, while others take large rolls.
7. What are
the uses and characteristics of speakers, headphones, and earbuds?
·
An
audio output device is a component of a computer that produces music, speech,
or other sounds, such as beeps. Three commonly used audio output devices are
speakers, headphones, and earbuds. Most personal computers and mobile devices
have a small internal speaker that usually emits only low-quality sound. Thus,
many users attach surround sound speakers or speaker systems to their
computers, including game consoles and mobile devices, to generate
higher-quality sounds for playing games, interacting with multimedia
presentations, listening to music, and viewing movies. Most surround sound
computer speaker systems include one or two center speakers and two or more
satellite speakers that are positioned so that sound emits from all directions.
·
When
using speakers, anyone in listening distance can hear the output. In a computer
laboratory or other crowded environment, speakers might not be practical.
Instead, users can listen through wireless headphones or earbuds or plug the
device in a port on the sound card, in a speaker, or on the front of the system
unit. With headphones or earbuds, only the individual wearing the headphones or
earbuds hears the sound from the computer. The difference is that headphones
cover or are placed outside the ear, whereas earbuds or earphones rest inside
the ear canal. Both headphones and earbuds usually include noise-cancelling
technology to reduce the interference of sounds from the surrounding
environment.
8. What are
the purposes and features of data projectors, interactive whiteboards, and
force-feedback game controllers and mobile devices?
·
A data projector is a device that takes
the text and images displaying on a computer screen and projects them on a
larger screen so that an audience can see the image clearly. For example, many
classrooms use data projectors so that all students easily can see an
instructor’s presentation on the screen. Some data projectors are large devices
that attach to a ceiling or wall in an auditorium. Some operating systems allow
projectors to be part of the network, which enables a presenter to operate
remotely via a network connection. Others, designed for the mobile user, are
small portable devices that can be transported easily. Two types of smaller,
lower-cost units are LCD projectors and DLP projectors. An LCD projector, which
uses liquid crystal display technology, attaches directly to a computer, and
uses its own light source to display the information shown on the computer
screen.
·
An interactive whiteboard is a touch-sensitive device, resembling a dry-erase
board, that displays the image on a connected computer screen. A presenter
controls the computer program by clicking a remote control, touching the
whiteboard with special digital pen and eraser, or writing on a special tablet.
Notes written on the interactive whiteboard can be saved directly on the
computer. Interactive whiteboards are used frequently in classrooms as a
teaching tool, during meetings as a collaboration tool, and to enhance delivery
of presentations.
·
Force-Feedback Game
Controllers and Tactile Output: Today’s joysticks, wheels, gamepads, and
motion-sensing game controllers also include force feedback, which is a
technology that sends resistance to the device in response to actions of the
user. For example, as you use the simulation software to drive from a smooth
road onto a gravel alley, the steering wheel trembles or vibrates, making the
driving experience as realistic as possible. These devices also are used in
practical training applications such as in the military and aviation. Some
input devices, such as smart phone, include tactile output that provides the
user with a physical response from the device. For examples, users may sense a
bumping feeling on their hand while scrolling through a smart phone’s contact
list.
9. What
output options are available for physically challenged users?
For users with mobility, hearing, or vision
disabilities, many different types of output devices are available.
·
Hearing-impaired users, for example can instruct
programs to display words instead of sounds. With the latest Windows operating
systems, users also can set options to make programs easier to use. The
Magnifier, for example, enlarges text and other items in a window on the
screen.
·
Visually impaired users can change Windows
settings, such as increasing the size or changing the color of the text to make
the words easier to read. Instead of using a monitor, blind users can work with
voice output via Windows Narrator. That is, the computer reads the information
that is displayed on the screen. Another alternative for visually impaired users,
is a Braille printer, which prints out information on paper in Braille letters.
