A.1.3—Tables, diagrams, bar charts and histograms

Tables keep exact values visible; bar charts compare categories; histograms show how continuous measurements are distributed; diagrams clarify structure or process.

Label axes and units, choose equal scales, include a key when needed and make the display match the variable type. Keep raw data available behind any summary.

Use a histogram for a distribution of cell diameters, but a bar chart for separate treatment groups; joining category bars can falsely imply continuity.

A polished graph cannot repair missing units, selective data or a misleading scale.