A line graph is used to spot trends in data over time. In order to produce a line graph, data is required. The data often comes in the form of a table. A student recorded how much time they spent ...

Consider the three graphs presented here. The first (above) shows year-by-year global temperatures since 1941 (source here). The black line shows the trend line for the entire chart. Does that ...

William Playfair, the father of data visualisation, changed the way we understand information. His bar graphs, pie charts, ...