1. Introduction

You should have all come across the term 'Garbage In, Garbage Out' (GIGO).

What it means is that if the data you put into your system is incorrect or of poor quality, then no matter how good your system is or how careful you are at setting up your queries, all you are going to get in return is poor quality, inaccurate information.

Over the next few pages we will be looking at the six factors which affect the quality of information.

You need to be able to remember each of them as well as provide sensible examples to demonstrate how problems can be caused.