DECK NI HUBS

• Computer: a special type of electronic calculating device capable of performing arithmetic and logical operations based on different programming languages and applications
• Characteristics of a computer:

  • Accurate
  • High-speed processing
  • Can store and retrieve information
  • Performs arithmetic and logical operations
  • Can do repeated tasks
• Classifications of Computers:

  • According to TYPES: Analog Computers, Digital Computers, Hybrid Computers
  • According to USES: Scientific Computers, Business-oriented Computers
• Limitations of computers:

  • Cannot create its own idea
  • Cannot combine ideas to form new ideas
  • Can detect errors but cannot completely correct them
  • Needs periodic maintenance
  • Experiences breakdowns such as fluctuations and power losses
• Elements of Computers:

  • Generic Architecture of Computers:
  • INPUT
  • OUTPUT
  • ALU (Arithmetic Logic Unit)
  • CU (Control Unit)
  • REGISTER
  • CPU (Central Processing Unit)
  • PRIMARY MEMORY UNIT
  • SECONDARY MEMORY UNIT
• Parts of Computers:

  • Input: information being fed to the CPU
  • CPU: Central Processing Unit responsible for all the computer’s activities
  • ALU: Arithmetic Logic Unit responsible for computations and decision making
  • CU: Control Unit responsible for CPU’s activities
  • Register: temporary storage data
  • Primary Memory Unit: internal storage of data (RAM - data temporarily saved, ROM - data permanently saved)
  • Secondary Memory Unit: external storage of data (CD, MD)
  • Output: desired information
• Output is data that has been processed into a useful form
• An output device is any type of hardware component that conveys information to one or more people
• Display devices visually convey text, graphics, and video information
• A monitor is packaged as a separate peripheral, such as an LCD monitor
• Liquid crystal display (LCD) uses a liquid compound to present information on a display device
• The quality of an LCD monitor or screen depends primarily on:

  • Resolution
  • Response time
  • Brightness
  • Dot pitch
  • Contrast ratio
• Resolution is the number of horizontal and vertical pixels in a display device
• The graphics processing unit (GPU) controls the manipulation and display of graphics on a display device
• Plasma monitors use gas plasma technology and offer screen sizes up to 150 inches
• Televisions are also a good output device, requiring a converter if connecting a computer to an analog television
• A CRT monitor is a desktop monitor that contains a cathode-ray tube and has a much larger footprint than LCD monitors
• A printer produces text and graphics on a physical medium, creating a hard copy or printout
• Before purchasing a printer, ask yourself a series of questions
• A nonimpact printer forms characters and graphics on a piece of paper without actually striking the paper
• An ink-jet printer forms characters and graphics by spraying tiny drops of liquid ink onto a piece of paper
• A photo printer produces color photo-lab-quality pictures, often using ink-jet technology
• A laser printer is high-speed, high-quality, and can print in color or black-and-white
• A multifunction peripheral (MFP) is a single device that prints, scans, copies, and in some cases faxes, sometimes called an all-in-one device
• A thermal printer generates images by pushing electrically heated pins against heat-sensitive paper
• A mobile printer is a small, lightweight, battery-powered printer that allows a mobile user to print from a notebook computer, smartphone, or other mobile device
• A label printer is a small printer that prints on adhesive-type material; a postage printer prints postage stamps, which can also be printed on other types of printers
• Plotters are used to produce high-quality drawings; large-format printers create photo-realistic quality color prints on a larger scale
• Impact printers form characters and graphics on a piece of paper by striking a mechanism against an inked ribbon that physically contacts the paper
• A dot-matrix printer produces printed images when tiny wire pins on a print head mechanism strike an inked ribbon; a line printer prints an entire line at a time
• An audio output device produces music, speech, or other sounds; most computer users attach speakers to their computers to generate higher-quality sounds for playing games, interact with multimedia presentations, listen to music, and view movies
• Headphones are speakers that cover or are placed outside of the ear; earbuds (also called earphones) rest inside the ear canal
• Some speakers are specifically designed to play audio from a portable media player, known as wireless speakers
• Voice output occurs when you hear a person’s voice or when the computer talks to you through the speakers; some websites dedicate themselves to providing voice output, often working with voice input; VoIP uses voice output and voice input
• Other output devices include data projectors, interactive whiteboards, force-feedback game controllers, and tactile output
• A data projector takes the text and images displaying on a computer screen and projects them on a larger screen; types include LCD projectors and Digital Light Processing (DLP) projectors
• An interactive whiteboard is a touch-sensitive device that displays the image on a connected computer screen
• Force-feedback sends resistance to the device in response to the actions of the user; tactile output provides the user with a physical response from the device
• Various methods of output include display devices, printers, speakers, headphones, earbuds, data projectors, interactive whiteboards, force-feedback game controllers, and tactile output
• Input is any data and instructions entered into the memory of a computer