Lecture 1 What Are Information Systems?

In This Lecture You Will Learn:

• The Elements of an IS
• The Role of Computer
• System Transformation
• General System Theory
• Characteristics of Systems
• Systems of the Real World

The Elements of an IS

Every IS has:

• A human activity that needs information
• An input method for entering data
• Some process that turns the data into information
• Some stored data
• An output method for representing information

The Role of the Computer

• Computers carry out tasks also done by people and by other technologies
  • Storage: signalman’s memory / hard disk
  • Display: battle of Britain map / PC screen
  • Calculation: mental arithmetic / program
  • Communication: telephone line / LAN
• Typical advantages of computers:
  • high speed, low cost, reliability,etc
• Wider questions that computer held for commercial activities.

1. How do we establish the business requirements for a new system?
2. What effect will the new system have on the organization?
3. How do we ensure that the system we build will meet its requirements?

System Transformation

• All useful systems transform their inputs into useful outputs
• For IS, both inputs and outputs are typically information
• This transformation is the whole reason for building and operating the system

Transformation Example

• McGregor’s Delivery Scheduling System may have inputs:
  • Information about orders, available stock, customer addresses, vehicle capacities…
• —and may have outputs:
  • Which orders to load on each vehicle, what route the vehicle should follow…
• How does this benefit McGregor?

General Systems Theory

• System
  • a very specific term
  • it is more than just computer system e.g. legal system, the system of parliamentary democracy, a reservation system, etc.
• A system is rather more than just anything that shows a degree of organization.

Characteristics of Systems

• Exists in an environment – situation
• Separated from its environment by some kind of boundary.
• Inputs and outputs – from & to different environment.
• Interfaces – allows communication between user & the system.

• IS are like any other kind of system
• Every system has:
  • Inputs and outputs
  • A purpose (related to transformation)
  • A boundary and an environment
  • Sub-systems and interfaces
  • Control using feedback and feed-forward
  • Some emergent property

Parts of a system, and their relationship to each other.

• Boundary and environment
  • Two systems may be closely related, may have identical boundary, but yet still distinct.
• Inputs and outputs
  • Purpose of system is to transform input into output, this is how they fulfill their objectives.

Input and outputs

Feedback

• One or more output of the system is sampled and feed back to the control unit.
• For example, a sensor samples the temperature in the main freezer compartment and this is feed back to the control unit.

Feed-forward

• It relies on sampling system’s inputs rather than outputs.
• For example, the Christmas toy business

Emergent properties

• The system possesses some feature or ability of its own that is not present in any of its components. e.g. components of a car.

Holistic concept

• Thinking about each system as a whole.

Systems of interest in this subject

• System can be natural or artificial.
• Human activity system.

• This subject is more concern with artificial kind of system.

Are Systems Real?

Maybe, maybe not!

• Systems thinking is useful because it helps to analyse and understand problems
• What matters are the understanding you achieve
• You can choose to see anything as a system, whether or not it really is one

Systems and the Real World

Summary

In this lecture you have learned about:

• What are the elements of an IS?
• The role of computer
• The process of system transformation
• The general system theory
• The characteristics of systems
• The relation between system and the real world