chapter 6 computer fluency
LED (light-emitting diode)
- use similar technology with a more advances backlighting technology -They produce better-quality images, are slimmer, and are more environmentally friendly as they require less power and use fewer toxic chemicals to manufacture. -Most new monitors are LED.
curved monitors
-It uses similar technology as flat-panel monitors except it has a concave screen that provides better viewing angles near the edges of the screen.
three types of flat panel monitors
-LCD -LED -OLED
optical scanner/scanner
-accepts documents consisting of text and/or images and converts them to matching-readable form -These devices do not recognize individual letters or images. Rather, they recognize light, dark, and colored areas that make up individual letters or images -Typically, scanned documents are saved in files that can be further processed, displayed, printed, or stored for later use.
duplex printing (basic distinguishing features of printers)
-allows automatic printing on both sides of a sheet of paper
input
-any data or instructions that are used by a computer -You provide input whenever you use system or application programs -You also can enter data and issue commands by pointing to items or using your voice. Other sources of input include scanned or photographed images.
multitouch screens
-can be touched with more than one finger, which allows for interactions such as rotating graphical objects on the screen with your hand or zooming in and out by pinching and stretching your fingers.
digital cameras
-capture images digitally and store the images on a memory card or in the camera's -Most digital cameras are also able to record video as well.
mouse
-controls pointer that is displayed on the monitor -mouse pointer usually appears in the shape of an arrow
image capturing devices
-create or capture original images -ex: digital cameras and webcams
3D printers/additive manufacturing
-create three-dimensional shapes by adding very thin layer after layer of material until the final shape is fully formed
ergonomics
-defined as the study of human factors related to things people use. -For computer users and manufacturers this means designing input and output devices to increase ease of use and to avoid health risks.
gamepads
-designed to be held by two hands and provide a wide array of inputs including motion, turning, stopping, and firing
game controllers
-devices that provide input to computer games. -
four basic types of optical scanners
-flatbed -document -portable -3D
output devices
-hardware used to provide or to create output -They translate information that has been processed by the system unit into a form that humans can understand. -most widely used: monitors, printers, and audio-output devices
input devices
-hardware used to translate words, numbers, sounds, images, and gestures that people understand into a form that the system unit can process -In addition to keyboards and mice, there are a wide variety of other input devices. These include pointing, scanning, image capturing, and audio-input devices.
contrast ratios
-indicate a monitor's ability to display images -It compares the light intensity of the brightest white to the darkest black. The higher the ratio, the better the monitor. Good monitors typically have contrast ratios between 500:1 and 2000:1
aspect ratio
-indicates the proportional relationship between a display's width and height -this relationship is expressed by two numbers separated by a colon (:)
output
-is processed data or information -output typically takes the form of text, graphics, photos, audio, and/or video
keyboard
-keyboards convert numbers, letters, and special characters that people understand into electrical signals. -These signals are sent to, and processed by, the system unit
personal laser printers
-less expensive and are used by a single user
three types of character and mark recognition devices
-magnetic-ink character recognition (MICR) -optical-character recognition (OCR) -optical-mark recognition (OMR)
size/active display area
-measured by the diagonal length of a monitor's viewing area
speed (basic distinguishing features of printers)
-measured in the number of pages printed per minute
DPI (dots per inch)
-measures printer resolution -higher the dpi, the better the quality of images produced
OLED (organic light-emitting diode)
-monitors replace the LED monitor's backlighting technology with a thin layer of organic compound that produces light -By eliminating the backlight, OLED monitors can be even thinner with better power efficiency and contrast ratios.
flatbed scanner
-much like copy machine -The image to be scanned is placed on a glass surface, and the scanner records the image.
resolution
-one of the most important monitor features -Images are formed on a monitor by a series of dots or pixels (picture elements) -Resolution is expressed as a matrix of these dots or pixels -the higher a monitor's resolution (the more pixels), the clearer the image produced
five scanning devices
-optical scanners -card readers -bar code readers -RFID readers -character and mark recognition devices
stylus
-penlike device typically used with tablets and mobile devices
two types of laser printers
-personal laser printers -shared laser printers
monitor/display screens
-present visual images of text and graphics -output is often referred to as soft copy
cloud printers
-printers connected to the Internet that provide printing services to others on the internet -ex: Google Cloud Print -you could use a smartphone from almost anywhere to send documents to be printed on a printer located at your home or school.
E-ink
-produces images that reflect light like ordinary paper, making the display easy to read
clarity
-refers to the quality and sharpness of the displayed images -It is a function of several monitor features, including resolution, dot pitch, contrast ratio, size, and aspect ratio.
basic distinguishing features of printers
-resolution -color capability -speed -memory -duplex printing
character and mark recognition devices
-scanners that are able to recognize special characters and marks -They are specialty devices that are essential tools for certain applications
optical-mark recognition (OMR)
-senses the presence or absence of a mark, such as a pencil mark -OMR is often used to score standardized multiple-choice tests.
document scanner
-similar to a flatbed scanner except that it can quickly scan multipage documents -It automatically feeds one page of a document at a time through a scanning surface
resolution (basic distinguishing features of printers)
-similar to monitor resolution -measure of the clarity of images produced -measured in DPI
wheel button
-some mice have a wheel button that can be rotated to scroll through information that is displayed on the monitor
audio-input devices
-sounds into a form that can be processed by the system unit -ex: microphone, human voice, music
plotters
-special-purpose printers for producing a wide range of specialized output -Using output from graphics tablets and other graphical input devices, plotters create maps, images, and architectural and engineering drawings. -Plotters are typically used by graphic artists, engineers, and architects to print out designs, sketches, and drawings.
inkjet printers
-spray ink at high speed onto the surface of paper. -his process produces high-quality images in a variety of colors, making it ideal for printing photos. -reliable and quiet
dot (pixel) pitch
-the distance between each pixel -the lower the dot pitch (the shorter the distance between pixels), the clearer the images produced
traditional keyboard
-these full-size keyboards are widely used on desktops and larger computers. -Traditional keyboards provide function keys, navigation keys, and a numeric keypad. Some keys, such as the Caps Lock key, are toggle keys. These keys turn a feature on or off. -Others, such as the Ctrl key, are combination keys, which perform an action when held down in combination with another key.
laptop keyboards
-these keyboards are smaller than traditional keyboards and are widely used on laptop computers. -While the precise location and number of keys may differ among manufactures, laptop keyboards typically have fewer keys, do not include a numeric keypad, and do not have a standard location for the function and navigation keys
thumb keyboards
-these keyboards are used on smartphones and other small mobile devices
virtual keyboards
-these keyboards are used primarily with mobile devices and tablets. -no physical keyboard
RFID (radio-frequency identification) tags
-tiny chips that can be embedded in most everything -these chips contain electronically stored information that can be read using an RFID reader located several yards away -The chips can be found in consumer products, driver's licenses, passports, and any number of other items. -They are widely used to track and locate lost pets; to monitor production and update inventory; and to record prices, product descriptions, and locations of retail items.
four different categories of keyboards
-traditional -laptop -virtual -thumb
audio-output devices
-translate audio information from the computer into sounds that people can understand -commonly used: speakers, headphones
printer
-translate information that has been processed by the system unit and present the information on paper.
Multifunctional devices (MFD)
-typically combine the capabilities of a scanner, printer, fax, and copy machine. -offer cost and space advantage -The reliability of multifunctional devices suffers because problems with one of the functional parts can make the entire device inoperable
robots
-use cameras, microphones, and other sensors as inputs
thermal printers
-use heat elements to produce images on heat-sensitive paper -These printers are widely used with ATMs and gasoline pumps to print receipts.
3D scanners
-use lasers, cameras, or robotic arms to record the shape of an object -Like 2D scanners, most 3D scanners cannot recognize light, dark, and colored areas
magnetic-ink character recognition (MICR)
-used by banks to automatically read those unusual numbers on the bottom of checks and deposit slips -A special-purpose machine known as a reader/sorter reads these numbers and provides input that allows banks to efficiently maintain customer account balances.
voice recognition systems
-uses a microphone, a sound card, and special software -these systems allow users to operate computers and other devices as well as to create documents using voice commands -These voice recognition systems can perform any number of operations including scheduling events on your calendar, composing simple text messages, and looking up facts on the web.
laser printers
-uses a technology similar to that used in a photocopying machine -Laser printers use a laser light beam to produce images with excellent letter and graphics quality
cordless/wireless mouse
-uses radio waves or infrared light waves to communicate with the system unit
optical-character recognition (OCR)
-uses special preprinted characters that can be read by a light source and changed into machine-readable code -a common OCR device is the handheld wand reader -These are used in department stores to read retail price tags by reflecting light on the printed characters.
optical mouse
-widely used -emits and senses light to detect mouse movement -traditionally the detected movements are communicated to the system unit through a cord
memory (basic distinguishing features of printers)
-within a printer is used to store printing instructions and documents waiting to be printed. -The more memory, the faster it will be able to print large documents.
popular game controllers
1. joysticks 2. gaming mice 3. gamepads 4. motion-sensing devices
flat-panel monitors
Compared to other types, they are thinner, are more portable, and require less power to operate.
smart cards
Many credit cards, known as smart cards, include additional security in the form of a microchip embedded in the credit card. This chip contains encrypted data that makes it nearly impossible for criminals to forge a duplicate card. Some chips require that you insert the card into a specialized reader, while others only require that you hold the card near the reader.
card readers
Nearly everyone uses a credit card, debit card, access (parking or building) card, and/or some type of identification card. These cards typically have the user's name, some type of identification number, and signature on the card. Additionally, encoded information is often stored on the card. Card readers interpret this encoded information.
magnetic card reader
The encoded information is stored on a thin magnetic strip located on the back of the card. When the card is swiped through the magnetic card reader, the information is read
bar code readers
These devices are either handheld wand readers or platform scanners. They contain photoelectric cells that scan or read bar codes, or the vertical zebra-striped marks printed on product containers.
Voice over IP (VoIP)
a set of standards or technologies that support voice and other types of communication over the Internet -Telephony, also known as Internet Telephony, is the VoIP application that uses Internet rather than traditional telephone lines to support voice communication.
gaming mice
are similar to traditional mice with higher precision, faster responsiveness programmable buttons, and better ergonomics
webcams
are specialized digital video cameras that capture images and send them to a computer for broadcast over the internet
joysticks
control game actions by users varying the pressure, speed, and direction of a control stick
motion-sensing devices
control games by user movements
scanning devices
convert scanned text and images into a form that they system unit can process
Ultra-high-definition television (UHDTV)
delivers a much clearer and more detailed wide-screen picture than regular HDTV. Because the output is digital, users can readily freeze video sequences to create high-quality still images. The video and still images can then be edited and stored for later use. This technology is very useful to graphic artists, designers, and publishers.
toggle keys
ex: caps lock key -these keys turn a feature on or off
combination keys
ex: ctrl key -perform an action when held down in combination with another key
carpal tunnel syndrome
found among heavy computer users, consists of damage to nerves and tendons in the hands.
printer output is called
hard copy
Repetitive strain injury (RSI)
is any injury that is caused by fast, repetitive work that can generate neck, wrist, hand, and arm pain
pointing devices
provide an intuitive interface with the system unit by accepting physical movements or gestures such as finger pointing or moving across the screen an converting these movements into machine-readable input
handwriting recognition software
translates handwritten notes into a form that the system unit can process
portable scanner
typically a handheld device that slides across the image, making direct contact
shared laser printers
typically support color, are more expensive, and are used (shared) by a group of users
touchpad
used to control the mouse pointer and to make selections
UPC (universal product codes)
widely used by retail stores to automate the processes to check out customers, to change product prices, and to maintain inventory records
MaxiCode
widely used by the United Parcel Service (UPS) and others to automate the process of routing packages, tracking in-transit packages, and locating lost packages
LCD (liquid crystal display)
widely used for older monitors and is typically less expensive