1. Introduction

The most basic way of viewing data is like this:

Item No. Sold
Shoes 5
Ties 2
Gloves 10

This is called 'tabulated data'.

Each row has a column to identify the data and another column to enter a data value. In this case it is tabulating the sales figures in a shop.

For just a few data items this is probably fine. You can see for example that quite a few gloves were sold compared to the number of ties sold.

But if the table gets any longer, then it becomes far more difficult to see patterns within the data or to get any sense of proportion.

This is where 'charts' or 'graphs' come in.

A chart or a graph displays the same information in a visual way. And people are far better at understanding images than long lists of data.