Chapter 1B

1
Chapter 1B

• Computer Basics

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Computer Basics

• Computer an multipurpose (electronic) device
  that accepts input, processes data, stores data,
  and produces output.
• Prior to 1940, a computer was defined as a
  person who performs calculations.
• The first modern computers emerged in 1940s.

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Most computer systems perform the following four
operations

• INPUT - computer gets information from an input
  device
• PROCESSING - the computer performs certain
  operations to the data
• Computer programs
• Instructions how to carry out tasks
• Central Processing Unit
• The brain of the computer
• OUTPUT - the computer shows the results after
  processing data
• STORAGE - stores the result somewhere inside the
  computer.

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Figure 1-12
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Memory vs. Storage
Difficulty comes because they are both measured
in the same units (bytes).
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Stored Program Concept

• series of instructions for a computing task can
  be loaded into a computers memory
• Transferring instructions (programs) from storage
  to memory
• LOADING

7
Application vs. System Software

• Application Software
• Is a set of program that helps a person carry out
  a task
• Word processor, games, video editing software
• System Software
• Primary purpose is to help the computer system
  monitor itself in order to function efficiently
• Controls and Coordinates Computer Operations
• Operating System

8
Computer Categories

• 1940s and 1950s no need for categories
• Mainframes
• 1968
• Minicomputers
• Used to describe smaller less expensive computer
  than mainframes
• 1971
• Microcomputers
• Introduction of home computers
• Microprocessors
• With technological changes the categories became
  blurred
• Personal computers (desktop, laptop), tablet
  computer, handheld computers, workstations,
  videogame consoles, mainframes, supercomputers,
  and servers.

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Personal Computers

• A personal computer is a microprocessor-based
  computing device designed to meet the computing
  needs of an individual

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Workstations

• The term workstation has two meanings
• An ordinary personal computer that is connected
  to a network
• A powerful desktop computer used for
  high-performance tasks

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Game Consoles

• A videogame console, such as Nintendos Wii,
  Sonys PlayStation, or Microsofts Xbox, are not
  generally referred to as personal computers
  because of their history as dedicated game devices

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The term Server

• Purpose
• Serve other computers on a network usually by
  supplying them with data
• Clients
• Several meanings possible
• Computer hardware (type of computer)
• Manufactures categorize their computers as
  servers
• Especially suited for storing and distributing
  data
• Software (software that provides a service)
• Combination of Hardware and Software

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Mainframes

• most widely used type by large businesses
• Multi-user System
• Hundreds or thousands of users can be using the
  system at the same time.
• Provide centralized data storage, processing, and
  management
• Cost several hundred thousand dollars

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Super Computers

• largest, fastest, most powerful most expensive
• massively parallel processors
• Hundreds if not thousands of processors to help
  do the work.
• Are often used for research
• Modeling weather, simulating nuclear explosions,
  breaking codes
• Cost - 500,000 up to 35 million

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Handheld Computer

• PDA (Personal Digital Assistants)
• Computing accessory
• Fits into a pocket
• Runs on batteries
• Personal applications
• Appointment book, address book, calculator,
  notepad, maps, e-mail, games, translators, other
  various applications
• Synchronize information with a personal computer

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Microcontrollers

• A microcontroller is a special-purpose
  microprocessor that is built into the machine it
  controls
• Microcontrollers can be embedded in all sorts of
  everyday devices
• Microwaves
• Washer machines
• Refrigerators
• Vehicles