CHAPTER 1- WHY COMPUTERS MATTER TO YOU:
BECOMING COMPUTER LITERATE
Why Should You Become Computer Literate?
- just by being a member of society you already know quite a bit about computers
Computer Literate: being familiar enough with computers that you understand their capabilities and
limitations and know how to use them
o You can use your computer more wisely and be a more knowledgeable consumer
o Computer literate employees are sought after in almost every vocation
o Becoming computer literate will help you better understand and take advantage of
o Understanding computers and their ethical, legal, and societal implications will make
you a more active and aware participant in society
Becoming A Savvy Computer User and Consumer
- Avoiding hackers and viruses: both can threaten a computer’s security, knowing how hackers
operate can help you avoid falling prey to them
- Protecting your privacy: knowing how to protect yourself from things such as identity theft
- Understanding the real risks: being able to separate the real privacy and security risks from
things you don’t have to worry about
- Using the internet and the Web wisely: finding information and finding good information are
two different things- being computer literate make the internet a powerful tool, and find the
information they need effectively
- Avoiding online annoyances: knowing how to avoid being overwhelmed by spam or junk mail.
There are some software programs you should install to avoid these annoyances
- Being able to maintain, upgrade, and troubleshoot your computer: understanding computer
terminology and keeping current with technology will help you better determine which
computers and devices match your needs
Being Prepared for Your Career
Information Technology (IT): field of study focused on managing and processing information and the
automatic retrieval of information. Includes computers, telecommunications, and software deployment.
Computers in Today’s Careers
Retail: Working in a Data Mine
Data Mining: the process of searching huge amounts of data with the hope of finding a pattern Ex. Large retailers often study the data gathered from register terminals to determine which products
are selling on a given day and in a specific location
- Managers use mined data to determine that if a certain product is to sell well, they must lower
its price-especially if they cut the price at one store and see sales increase.
- Allows retailers to respond to consumer buying patterns
Business Data on the Go
- For UPS, package tracking begins the sender drops off a package and the company creates a
“smart label” for the package
- These devices use Bluetooth technology – a type of wireless communication to transmit the
scanned data through radio waves to a terminal. This terminal then sends the data across a
wireless network where it is recorded in the UPS data base
- GPS positioning, infrared scanners and an electronic pad to capture customer signatures- this
allows UPS customers to track their packages
Arts: Ink, Paints, and a Notebook?
- Some art students believe that because they’re studying art there is no reason for them to study
computers, however, they need computers to sell their work
- using computers in the arts and entertainment field goes far beyond using the internet
- dance and music programs use computers to create new performances for audiences
- not all art is on a canvas, many use computers with software programs such as Adobe Illustrator,
Photoshop and Corel Painter
Video Game Design: A Long Way from Pac-Man
- revenues from video game sales in the U.S. are not larger than the movie industry’s box office
- because computer games are best developed for a local market by people native enough to that
market, game development will most likely stay in the U.S. instead of being offshored (sent to
other countries)as many other types of programming jobs have been
Education: Teaching and Learning
- as an educator, being computer literate will help you integrate computers constructively into
lesson plans for your students and use technology to interact with them
Law Enforcement: Put Down That Mouse- You’re Under Arrest!
- Computers are being used in police cars and crime labs to solve an increasing number of crimes
ex. Facial reconstruction systems can turn a skull into a finished digital image of a face, allowing
investigators to proceed far more quickly with identification - Computer Forensics: growing, specifically analyzes computer systems with specific techniques
to gather potential legal evidence
- Computers are also used in training law enforcement officers to be more effective
Digital Home : having an appropriate computer and digital devices that are all connected to a home
Media Computer: a computer is the nerve centre of any digital home, allowing you to interface with al
the different digital devices you have connected to the network
TV tuner: allows your computer to receive television channels from a cable connection and display them
on your computer monitor
Blu-ray, DVD, and CD players and recorders: to make it easy to transfer your audio or video files from
one device to another, Blu-ray and DVD/CD players and recorders allow you to play all kinds of optical
Network Adapter: device that is installed in your computer and allows it to communicate with other
devices on a network
A Network: unless you are going to view digital and audio files only on your computer, you will need a
network to transfer files easily to other devices(such as television) in your home.
An internet-ready digital television: newer plasma and organic light emitting diode (OLED) televisions or
high definition tvs are an important part of any digital home because they are the best way to show off
all your digital media
A universal Remote: single remote control that works with any infrared- controlled device and allows
you to access media such as MP3 files no matter where in the house it is stored.
Military Careers: Drive that Drone
- The U.S. military branches have some of the most highly technological projects ever developed
- Ex. The Air Force employs unmanned aerial vehicles, called UAVs or drones, to perform
surveillance operations and to deliver missiles.
- Unmanned drones can be controlled remotely, even at distances of thousands of miles, by
modern avionics systems
Agriculture: High-Tech Down on the Farm
- Ranchers face many challenges in modern meat production, they must look out for and prevent
outbreaks of diseases such as hoof and mouth, mad cow, and E. coli.
- Fortunately outbreaks can be managed and minimized with the use of radio frequency
identification tags (RFID tags).
o these are small versions of the roadway electric toll systems used in many states to
collect tolls automatically as drives pass through toll stations Automotive Technology: Sensors and CPUs
- automotive technicians are required to have knowledge of a range of tools
- people considering to have a career in automotive repair today require a sophisticated level of
computer literacy as well
- automotive technicians must be able to update documentation through the Internet, use
computer data bases to learn about common problems and solutions, and se computer systems
to interface with and run diagnostics on all the different automotive computer systems
Medicine: Technologies of Today and Tomorrow
- in addition to being an integral part if many medical research projects, computers are helping
doctors and nurses learn their trades
- medical students now have access to better training opportunities thanks to a computer
technology called a patient simulator – life sized, computer controlled mannequins that can
speak, breathe and blink (their eyes to respond to external stimuli)
o they have a pulse and a heartbeat , and they respond just like humans to procedures
such as the administration of intravenous drugs
o patient simulators allow health care students to practice medical procedures without
risk of injury or death to real patients
- even more exciting than patient simulators is the work being done on modeling complete
human biological systems
o it now is a global public domain effort (not covered by copyright) in which bioengineers
are creating realistic computer simulators of all simulations of all systems and features
of the human anatomy
o a doctor manipulates controls that move the robotic instrument tips inside the patient
o this shows what surgeons might see as they operate on the patient
Medicine: The Chip Within
- researchers are experimenting with implantable chips such as this one to repair nerve damage
and restore movement or sensation to parts of the body
- the MIT eyeball chip is a retinal implant that may restore at least partial vision to certain groups
of legally blind patterns
- no bigger than the period at the end of this sentence , the Hitachi u chip can hold digital
information, which can be read when it passes a detector
Science: Simulating Reality
- software that combines radar information in new ways increases the accuracy of tornado
predictions and allows for earlier warning of threatened towns
- a digital re-creation of the ruins of Pompeii allows archaeologists to study the ruins without
even being there, as well as re-create Pompeii as it looked before the devastation Nanotechnology: careers yet to come
- developments in computing based on the priciples of nanoscience are being touted as the next
big wave in computing
- the realm of science focuses on small objects, nanoscience- involves the study of molecules and
structures (called nanostructures) that range in size from 1 to 100 nanometers
- prefix nano stands for one billionth- one billionth of a meter
- nanotechnology- the science of using nanostructures to build devices on an extremely small
o limited to improving existing products, such as enhancing fibers used in clothing with
coatings so that they repel stains, resist odors or stop wrinkles
Psychology: you should smile… now
- Affective Computing – computing that relates to emotion or deliberately tries to influence
- Ex. Once project to emerge is the emotionally social prosthesis (ESP)
o Developed to help people with autism, wearable system that isolates the movements
and facial expressions of people, interprets their moods, and intents and
communicates information back to the user
- Robots with articulated joints that mimic human limbs can balance, stand, walk and even hug
Understanding the Challenges Facing a Digital Society
- Although computers offer us a world of opportunities, they also pose ethical, legal, and moral
challenges and questions
o Should the government be allowed to monitor your activities in public places to help
keep the country secure?
o Advances in technology are allowing surveillance to become smaller and less noticeable,
do you know if someone is watching you?
o Many employees don’t know that employers have the right to monitor email and
network traffic on the systems they use at work because those systems are provided at
the employers expense for the sole purpose of allowing employees to do their jobs.
Should employers have the right to know?
CIS 1200 – Chapter 2
- A computer is a data-processing device that performs 4 major functions:
- 1. Input: It gathers data, or allows users to enter data.
- 2. Process: It manipulates, calculates, or organizes that data into information.
- 3. Output: It displays data and information in a form suitable for the use. - 4. Storage: It saves data and info for later use.
- What’s the difference between data and information: In computer terms, data is a
representation of a fact, a figure, or an idea. Data can be a number, a word, a picture, or even a
recording of a sound. The name Zoe is a piece of data. Information is data that has been
organized or presented in a meaningful fashion. Contact listing’s showing Zoe can be reached by
phone at (713) 555-5555 makes previous data suddenly become useful, it then becomes
- How do computers interact with data and information: Computers are excellent at processing
(manipulating, calculating, or organizing) data into information. To get a student ID card
requires you provide personal data (name and address). Then a picture is taken (collecting more
data). This information is processed and then the organized output of the data is represented as
information on a physical identification card.
- How do computers process data into information? Computers work exclusively with numbers
(no words). To process data into information, comps need to work in a language they understand.
This language is called binary language, and it consists of two digits: 0 and 1. Each 0 and 1 is a
binary digit, or bit for short. Eight bits combine to create one byte. In comps, each letter of the
alphabet, each number, and each special character (@) consists of a unique combo of eight bits.
- What else can bits and bytes be used for? Bits and bytes aren’t only used as the language that
tells the comp what to do, but also they’re what the comp uses to represent the quantity of data
and information that it inputs and outputs. To make it easier to measure the size of data files, we
use units of measurement like: Kilobytes (1000 bytes), megabyte (1 million bytes), gigabyte (1
billion bytes), and terabyte ( 1 trillion bytes). Today, most PC’s can store terabytes of data;
business comps can store a petabyte (one thousand terabytes). Google processes more than 1
terabyte of generated data per hour.
- How does your computer process bits and bytes? The computer uses a combo of hardware and
software to process data into information and enables one to complete tasks like writing or
playing games. Hardware is any type of the comp you can physically touch. Software are the
computer programs and applications that run on the computer. Application software is the set of
programs you use on a comp to help carry out tasks like writing a paper. System software is the
set of programs that enables the computer’s hardware devices and application software to work
together. The most common system software is the operating system – the program that controls
the way in which the computer system functions. It manages the hardware of the computer system
- Are all computers the same? There are two basic designs of comps: portable and stationary. A
notebook comp (laptop) is a portable comp that has a keyboard, monitor, and other devices
integrated into a compact shell. Notebooks are powered by a battery or an AC adapter. A
netbook is a small version of a notebook (7-10 inches wide) and has a longer battery life than a
notebook. A tablet PC is similar to a notebook, but the monitor swivels and folds flat. Users
then issue commands with a stylus and input text via a virtual keyboard. A tablet computer is a mobile comp integrated into a flat multitouch-sensitive screen. A desktop computer is intended
for use at a single location (stationary) and use peripheral devices – a component, such as a
monitor or keyboard that is not directly integrated into the comp. An all-in-one computer
(iMac) doesn’t use a separate tower, because these comps house the processor and memory into
the monitor unit.
- Other types of computers? There are computers that you will likely never come into contact
with: A mainframe is a large, expensive comp that supports hundreds of users simultaneously.
Used mainly in offices where many ppl are working on similar operations. Mainframes excel at
executing many different comp programs at the same time. A supercomputer is a specially
designed comp that can perform complex calculations extremely fast. Supercomputers are used
in situations in which complex models requite intense mathematical calculations are needed
(weather forecasting). The main difference between a supercomputer and mainframe is that
supercomputers are designed to execute a few programs as quickly as possible, where mainframes
are designed ot handle many programs running at the same time, but at a slower pace. An
embedded computer is a specially designed computer chip that resides in another device, such
as your car. Embedded comps are self-contained comp devices that have their own programming
an typically don’t receive input from an individual.
- Input Devices: An input device enables you to enter data (text, images, sounds) and instructions
(user responses) into the comp. A keyboard is used to enter typed data and commands, and a
mouse is used to enter user responses. Other input devices include microphones, scanners, and
digital cameras, which input sounds, non-digital text, and digital images, respectively.
- Are all keyboards the same? Most comps come with a QWERTY keyboard, which is the
standard English-language keyboard layout. The qwerty layout was originally designed for
typewriters and was meant to slow typists down and prevent the keys from jamming. Although
the qwerty layout is considered inefficient, efforts to change to more efficient layouts (the Dvorak
keyboard); haven’t been met with public interest. This alternative keyboard puts the most
commonly used letters on “home keys,” which are the keys in the middle row of the keyboard.
You can change to the Dvorak layout without buying a new keyboard by using the Windows OS
and changing the keyboard layout. This layout can be beneficial for ppl who suffer carpal tunnel
syndrome due to it being a lesser strain on the hands.
- Notebook keyboards: Smaller notebook keyboards (14” under) are more compact than standard
keyboards and have fewer keys. To retain functionality, many of the notebook keys have
alternative functions (i.e. no separate number pad and use function key combos with number keys
to serve as an ulterior method of performing an action).
- Alternative Keyboards: Flexible keyboards are useful if one wishes to have a full-size keyboard
for their notebook. It can be rolled up and plugged in via a USB port. Virtual laser keyboards
project the image of a keyboard and sensors detect motion of the user’s fingers as they type on a
flat surface. Data is transmitted via Bluetooth technology, which is a wireless transmission
standard that facilitates the connection of electronic computing devices, i.e. smartphones and
comps to peripheral devices such as keyboards and headsets. Gamers love keyboards like the
DX1 from Ergodex, which allows for placement of the keys in nay position on the keyboard pad and the keys can be programmed to execute individual keystrokes or macros (a series of tasks) to
perform specific tasks.
- Effectively using a keyboard: Function keys act as shortcut keys you press to perform special
tasks (referred to as “F” keys, i.e. F1). Each software application has its own set of tasks assigned
to various function keys. The F2 key moves test in Word but allows editing of the active cell in
Excel. Many keys are universal: the F1 key is the help key in most applications. The Control key
(Ctrl) is used in combo with other keys to perform shortcuts and special tasks. Holding down the
Ctrl key while pressing B adds bold format to selected text The Insert key is a toggle key because
its function changes between one of two options each time it’s pressed. Toggle on: the Insert key
inserts new text within a line of existing text. Toggle off: the Insert key replaces existing
characters with new characters as you type. Other toggle keys include the Num Lock key and the
Caps lock key. The Windows key is specific to the Windows OS. Used alone, it opens the Start
menu, although you can use it in combo with other keys to perform shortcuts (Windows key + M
= minimizes all windows).
- All conventional keyboards connected via wires? Wireless keyboards provide additional
flexibility since there aren’t wires. Wireless keyboards are powered by batteries and these
keyboards send data to the comp using a form of wireless technology that uses radio frequency
(RF). A radio transmitter in the keyboard sends out radio wave signals that are received through
a small receiving device plugged into the USB port or a Bluetooth receiving device that is
contained in the system unit. RF keyboards used with home comps can work from 6-30 ft away,
while keyboards used in auditoriums can be placed 100 ft away from the comp.
- What kind of Mice are there? The most familiar mouse type is the optical mouse. An optical
mouse uses an internal sensor or laser to detect the mouse’s movement. The sensor sends signals
to the comp, telling it where to move the pointer on the screen. This type of mouse doesn’t
require a mouse pad. Most mice have two or three buttons that enable you to execute commands
and open shortcut menus. Many mice have additional programmable buttons that let you quickly
maneuver through web pages (Naga Epic). The Cyborg RAT9 is customizable to fit any size
hand and grip style.
- Wireless Mice? Wireless mice use batteries and send data to the comp by radio frequency or
Bluetooth. A wireless keyboard and mouse usually can share the same RF receiver. Small,
compact devices like the MoGo Mouse are designed for portability. It fits into a peripheral slot
on the side of a notebook, which stores, protects, and charges it.
- Other tasks possible with a mouse? One some new mouse models, Microsoft and Logitech
provide features such as: Magnifier: pulls up a magnification box to enhance viewing of hard to
read images (useful for ppl with disabilities). Web search: Allows for quick highlighting of a
word or phrase and then press the search button on the mouse to start a Web search. File
storage: Includes a wireless USB receiver that contains flash memory to store/back up your files.
- Notebook computers include a mouse? Most notebooks have an integrated pointing device such
as a touch pad/ track pad. Most touch pads are sensitive to taps, interpreting them as mouse clicks. Many notebooks also have buttons beneath the pads to record mouse clicks. Some
notebooks incorporate a trackpoint device, a small, joystick-like nub that allows you to move the
cursor with the tip of your finger.
- Input devices used with games? Game controllers, such as joysticks, game pads, and steering
wheels are also considered input devices because they send data to the comp. Game controllers
similar to the ones used on the Xbox 360 are also available for use with comps. Force-feedback
joysticks and steering wheels deliver data in both directions. They translate your movements to
the comp and translate its responses into forces on your hands.
- How else can I input data and commands: A touch screen is a display screen that responds to
commands initiated by a touch with a finger or stylus. Tablet PC’s were one of the first devices
with touch-screen capabilities. Another way to input data is through use of a digital pen. This
pen works in conjunction with a flash drive (electronic storage device that connects to a USB
port). You can write with the pen on any conventional paper. The pen captures your writing and
then wirelessly transmits and stores it in the flash drive. You can then use the flash drive to
translate your writing into digital text.
- Input digital images into a computer? Digital cameras and cell phones are common devices for
capturing pictures and all are considered input devices. These devices either connect to with a
data cable or transmit data wirelessly. The comp automatically recognizes these devices when
they’re connected and makes the input of the digital data to the comp simple and easy. Scanners
also input images. They work like a photocopy machine, but instead of generating the image on
paper, they create a digital image.
- Capture live video from a computer or device? A webcam is a small camera that sits on top of
a computer monitor or is built into the device. Webcams are able to capture still images, but are
used mostly for capturing and transmitting live video (sometimes in HD). Videoconferencing
technology allows a person using a comp with a webcam and mic to transmit video and audio
across the Internet. Video call sites like ooVoo make it easy to videoconference with as many as
- Ethical Computing: The Computer Ethics Institute developed the Ten Commandments of
Computer Ethics, which is widely cited as a benchmark for companies that are developing
computer usage and compliance policies for employees. These guidelines are applicable for
schools and students as well. They are as follows:
- 1. Avoid cuasing harm to others when using comps
- 2. Don’t interfere with other ppl’s efforts at accomplishing work w/ comps.
- 3. Resist the temptation to snoop in other ppl’s comp files.
- 4. Don’t use comps to commit theft.
- 5. Agree not to use comps to promote lies.
- 6. Don’t use software (or make illegal copies for others) w/o paying the creator for it.
- 7. Avoid using other ppl’s comp resources without appropriate authorization or proper
compensation. - 8. Don’t claim other ppl’s intellectual output as your own.
- 9. Consider the social consequences of the products of your comp labour.
- 10. Only use comps in ways that show consideration and respect for others.
- The US has enacted laws that support some of these guidelines, such as Guideline 6, the breaking
of which would violate copyright laws and Guideline 4, which is enforceable under numerous
federal and state larceny laws. Other guidelines, however, require subtler interpretation as to
what behaviour is unethical because there are no laws designed opt enforce them.
- Why would I want to input sound to my computer? You can conduct audio conferences with
work colleagues, chat with family and friends over the Internet instead of using a phone, record
podcasts, and more. Inputting sound to your computer requires using a microphone – a device
that allows you to capture sound waves and transfer them to digital format on your comp. Most
notebooks come with built-in mics, and some desktop comps come with inexpensive mics.
- What types of mics are available? Unidirectional mics pick up sound from only one direction.
They’re best used for recording podcasts with a single voice or making phone calls over the
Internet with only one person. Omnidirectional mics pick up sounds from all directions at once.
They’re best used for recording more than one voice, such as during a conference call.
Bidirectional mics receive sound equally from the front and back of the mic, and are especially
good for interviews. Clip-on mics (called lavalier microphones) are useful in environments such
as presentations, where you need to keep your hands free. Close-talk microphones, which are
usually attached to a headset, facilitate using speech-recognition software, videoconferencing, or
making phone calls. With a mic attached to headset, your hands are free to perform other tasks,
and the headset allows you to listen as well.
- Input devices available to people with disabilities? For visually impaired users, voice
recognition is an obvious option. For those users whose visual limitations are less severe,
keyboards with large keys are available. Keyboards that display on a touch screen can make
input easier for some individuals. These keyboards are displayed as graphics on the computer
monitor. There are also keyboards designed for ppl who can only use one hand, such as the
Maltron keyboard. Ppl with motor control issues can use special trackballs that can easily be
manipulated with one finger and can be attached to almost any surface, including a wheelchair.
- When arm motion is restrained, head-mounted pointing devices can be used. These involve
cameras on the monitor and a device attached to the head. When the user moves his head, the
camera detects the movement, which control the cursor on the screen. In this case, mouse clicks
are controlled by a switch that can be manipulated by the users hands or feet.
- Output Devices: An output device enables one to send processed data out of their comp in the
form of text, pics, sounds, or video. One common output device is a monitor or display screen,
which displays text, graphics, and video as soft copies (only visible on screen). Another common
output device is a printer, which creates hard copies (you can touch) of text and graphics.
Speakers would be considered output devices for sound.
- - Different types of monitors? The most common type of monitor is a liquid crystal display
(LCD). An LCD monitor, also called a flat-panel monitor, is light and energy efficient. Some
newer monitors used light-emitting diode (LED) technology, which is more energy efficient, and
may have better colour accuracy and thinner panels than LCD. These flat panel monitors have
replaced the cathode ray tube (CRT) monitor. CRT monitors are difficult to find or buy because
they’ve become legacy technology, or computing devices or peripherals that use techniques,
parts, and methods from an earlier time that are no longer popular. Although legacy technology
may still be functional, it is quickly being replaced by newer technological advances. Organic
light-emitting diode (OLED) displays use organic compounds that produce light when exposed
to an electric current. Unlike LCD and LED, OLED doesn’t require a backlight to function and
therefore draw less power and have a much thinner display. They are also brighter and more
environmentally friendly than LCD’s. Because of their lower power needs, OLED displays run
longer on a single battery charge than do LED’s, which is why this technology is currently being
used in small screens of mobile devices.
- How do LCD monitors work? Monitor screens are grids made up of millions of tiny dots, each
of which is called a pixel. Illuminated pixels create the images ppl see on their monitors. Each
pixel is actually composed of three subpixels of red, blue, and green. LCD monitors are made of
two or more sheets of material filled with a liquid crystal solution. A fluorescent panel at the
back of the LCD monitor generates light waves. When electric current passes through the liquid
crystal solution, the crystals move around and either block the fluorescent light or let the light
shine through. This blocking or passing of light by the crystals causes images to form on the
- Factors that affect the quality of an LCD monitor: When choosing an LCD monitor, thee are
several factors to consider, such as aspect ratio and resolution. The aspect ratio is the width-to-
height proportion of a monitor. Traditionally, aspect ratios have been 4:3, but newer monitors are
available with an aspect ratio of 16:9 or 16:10. The screen resolution reflects the number of
pixels on the screen. An LCD monitor may have a native resolution of 1600 X 1200 meaning it
contains 1600 vertical columns with 1200 pixels in each column. The higher the resolution, the
sharper and clearer the image will be. You can change the resolution of an LCD monitor beyond
its native resolution, but the images will become distorted. Other factors to consider with quality
of an LCD are:
- Contrast ratio: This is a measure of the difference in light intensity between the brightest white
and the darkest black that the monitor can produce. If the contrast ratio is too low, colours tend to
fade when you adjust the brightness to a high or low setting. A contrast ratio between 400:1 and
1000:1 is preferable. Some monitors may sport a dynamic contrast ratio that may be 10,000:1 or
50,000:1. This measurement is taken when the backlight is turned off completely; normal
contrast ratio measurements have the backlight dimmed to its lowest setting but not completely
off. In normal use, the backlight is not turned off, so the dynamic contrast ratio is not a relevant
measure, unless one is using an LED monitor.
- - Viewing angle: A measurement in degrees that tell how far you can move to the side of (or above
or below) the monitor before the image quality degrades to unacceptable levels. For monitors
that measure 17 inches or more, a viewing angle of at least 150 degrees is usually recommended.
- Brightness: Measured as candelas per square meter, brightness is a measure of the greatest
amount of light showing when the monitor is displaying pure white. A brightness level of 300
cd/m2 or greater is recommended.
- Response time: This is the measurement (in milliseconds) of the time it takes for a pixel to
change colour. A lower response time value means faster transitions; therefore moving images
will appear less jerky on the monitor.
- Bigger screen size always better? The larger the panel, the larger number of pixels it can
display. For example, a 27-inch monitor can display 2560 x 1440 pixels, while a 21.5 inch
monitor may only be able to display 1680 x 1050 pixels. Larger screens can also allow you to
view multiple documents or Web pages at the same time, creating the effect of using two separate
monitors side by side. However, cost is an issue. Buying two smaller monitors might be cheaper
than buying one large monitor.
- Other features to look for in an LCD monitor? Some monitors (especially notebooks) come
with built-in features like speakers, webcams, and mics. A built-in multiformat card reader is
convenient to display images directly on the monitor or to download pics quickly from a camera
memory card to the PC. LCD monitors should also have a USB port. This enables one to
connect extra peripherals easily w/o reaching around the back of the PC. If one wishes to connect
a gaming console or DVD player, monitors with video ports is essential for easy access.
- How to show output to a large group of people? It is good to use a projector, a device that can
project images from your screen onto a wall or viewing screen. Projectors are commonly used in
business and educational settings like conference rooms. Some projectors (3M MPro 150) are
small enough to fit in the palm of your hand. These would be ideal for business ppl that have to
make presentations at client locations. Entertainment projectors, such as the Wonderwall,
include stereo speakers and an array of multimedia connectors, making them a good option to use
for in the home. If a laptop is equipped with an HDMI port, it can be connected directly to an
HDTV. Although you could connect your laptop with a DVI port, by using HDMI, you only
need the one cable, eliminating the need for additional audio cables.
- How Touch Screens work: Touch-screen technology was developed in 1971, and used primarily
with ATMs and fast-food order displays. Three basic systems are used to recognize a persons’
touch: resistive, capacitive, and surface acoustic wave. All of these systems require the basic
components of a touch-responsive glass panel, controller, and software driver, combined with a
display and a comp processor. The resistive system maps the exact location of the pressure point
created when a user touches the screen. The capacitive system uses the change in the electrical
charge on the glass panel of the monitor that is created by the user’s touch to generate a location.
Surface acoustic wave system uses two transducers (electrical devices that convert energy from
one form to another) that are placed along the x and y axes of the monitor’s glass plate.
Reflectors, which are also placed on the glass, are used to reflect an electrical signal sent from the
sending transducer to the receiving transducer. The receiving transducer determines whether the signal has been disturbed by a touch event and locates the touch instantly. With all three systems,
the display’s software driver translates the touch into something the operating system can
- Because the resistive system uses pressure to register a touch, it doesn’t matter if the touch is
created by a finger or stylus. A capacitive system must have a conductive input, so a finger is
required. The surface acoustic wave system allows touches by any object. iPhone introduced a
feature with touchscreen’s called multi-touch. Many tablets and smartphones now have this
feature and their screes have the capacitors arranged in a coordinate system so the circuitry can
sense changes at each point along the grid. Consequently, every point when touched on the grid
generates its own signal, and can do so even simultaneously as other signal is also being
generated. The signals are then relayed to the device’s processor. This allows the device to
determine the location and movement of simultaneous touches in multiple locations.
- What are the different types of printers? There are two primary categories of printers: inkjet
and laser, both of which are considered nonimpact printers. A nonimpact printer sprays ink or
uses laser beams to transfer marks onto paper. Most have totally replaced impact printers. An
impact printer has tiny hammer keys that strike the paper through an inked ribbon, making
marks on the paper. The most common impact printer is the dot-matrix printer. The dot-matrix
printer for most ppl is now only legacy technology.
- Advantages of inkjet printers? An inkjet printer is the standard printer found in most homes.
They are affordable and produce high-quality colour printouts quickly and quietly. They spray
tiny drops of ink onto paper and are great for printing black and white text as well as colour
images. When loaded with the right paper, high-end inkjet printers can print images that look like
professional-quality photos. One thing to consider when buying an inkjet is the type and cost of
the ink cartridges the printer needs. Some printers used two cartridges: black and colour. Other
printers use four or more cartridges, typically black,