Information Systems Fundamentals

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Information Systems Fundamentals

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What is an Information System?

• Information - data that is meaningful or useful
  to someone
• System - a group of components that work together
  for a common purpose
• Information System - a collection of components
  that work together to provide information to help
  in the operation and management of an
  organization.

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The Goal of an Information System

• To have the right information at the right time.

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The Value of Information

• Dimensions of information
• Time
• Timeliness
• Currency
• Content
• Accuracy
• Relevance
• Completeness
• Form
• Level of detail
• Form of presentation

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Information System Functions

• Input
• Storage
• Processing
• Output

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Components of a Computer-based Information System

• Hardware - the computer and related equipment
  used in the IS.
• Software - the instructions that tell hardware
  what to do.
• Data / information - the data that is kept in the
  IS and used by software and people.
• Personnel - the users and operators of the IS.
• Procedures - the instructions for how people
  should use the IS.

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Information System Hardware

• Computer an electronic device that can store
  data and follow a set of instructions called a
  program.
• Hardware devices include
• Input and output devices
• Primary storage
• Central processing unit
• Secondary storage devices
• Communication devices

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Input/output Devices

• Input and output devices are the link between the
  IS and the people who use them.
• An input device accepts data from outside the
  computer and converts it into an electronic form
  for use in the IS.
• An output device converts the electronic data
  from the IS into a form that can be used outside
  the system.

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Primary Storage

• Primary storage or internal storage is the
  memory of the computer. Similar to our own
  short term memory, primary storage is temporary
  and stores the data and instructions that the
  computer is currently working on.
• The main chips that are used for primary storage
  are called random access memory or RAM.

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Central Processing Unit

• The central processing unit (CPU) or processor,
  carries out the instructions in the program and
  directs the other parts of the system.
• The chip that comprises the CPU for a PC is
  called the microprocessor.

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Secondary Storage

• Secondary storage stores data on a more permanent
  basis.
• Typical secondary storage devices include hard
  disk, floppy disk drive, CD-ROM drive, and ZIP
  drive among others.

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Communications Hardware

• Communications hardware is all devices which are
  used to connect components of the IS so that they
  may communicate data between themselves and
  other systems.
• A configuration of computers that are connected
  together is called a network.

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Networks

• Local area network (LAN) - a network that is
  located in a small area such as a building or
  collection of nearby buildings.
• Wide area network (WAN) - a network that is
  spread out over a large geographic area.

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Networks

• Metropolitan area network (MAN) - a network that
  covers a city or metropolitan area.
• Global area network (GAN) - a network that is
  spread out around the world, crossing
  international boundaries.

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Benefit of Networks

• Share resources
• Data
• Programs
• Devices
• Provide means for security
• Enhance communication

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Information System Software

• System software programs that make computers
  usable such as communications software and
  operating systems.
• Application software programs designed to meet
  a specific need such as payroll, inventory
  control, and word processing.

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Data Versus Information

• Data - a fact, number, word, image, picture or
  sound
• Information - data that has been processed or
  organized to have meaning or useful to someone

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Information Systems Users

• User (or end-user) - a non-computer professional
  who use a computer information system for their
  work or daily lives. (Most of us!)
• Computer professional - a person with a certain
  amount of computer expertise who works with the
  technical or business aspects of a computer.
  Examples include programmers, systems analysts,
  computer salespeople, etc.

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Connecting Users to Information

• Networks
• Internet
• World wide web
• Intranet

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Procedures for Information Systems

• Procedures are the instructions that tell the
  users and operators how to use the system.
• Not only do they instruct the personnel how to
  use the system, but they also provide standards
  of use.
• They also provide information for what to do if
  the system does not function normally.

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Benefits of Information Systems

• Better information - can be used reliably to
  support decision making.
• Improved service - can work 24/7 at rates faster
  than any human for the most tedious of tasks.
• Increased productivity - allow people to be more
  productive.

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References

• Nickerson, R. Business and Information Systems.
  Reading, Mass. Addison-Wesley, 1998.