7 Unit summary

7.1 What have you learnt in this unit?

This unit began by exploring some basic issues involving computers:

• the nature of data and information;
  
• why human beings need (and want) computers;
  
• the prevalence of computers in modern life.
  

The unit looked briefly at how a computer-based society affects the average person who (whether he or she knows it or not) has a persona that consists of data about them held by many diverse organisations.
Much of this unit consisted of case studies illustrating the possibilities for computer use. They raised some of the issues posed by computing technologies, such as:

• the distinction between data and information;
  
• what computers can do with data to produce information;
  
• how computers can be used to work with data and search for it, control machines, and support commercial operations.
  

There are a number of themes running through this unit.

• Data requires encoding.
  
• In order to function, a computer requires data which may be stored in databases.
  
• Data has to be transmitted from place to place.
  
• At the heart of a computer system there are one or more programs.
  
• Many current computer systems are distributed, in that they consist of a number of computers which cooperate and communicate with each other in order to function.
  
• Information has to be fit-for-purpose.
  
• Security and trustworthiness are major concerns with many systems.
  
• Computer systems also have drawbacks and adverse effects. They also have social, political, legal and ethical implications.
  

You should be able to define the following terms in your own words.

case study	hit
computer	information
computer program	internet
computer system	keyword
data	parameter
database	perceptual data
database server	search engine
distributed system	sensation
gateway	sign/symbol
global positioning system (GPS)	World Wide Web (the web)