Bar Charts

Bar charts are great for comparisons. To judge their end points, the bars should begin at a zero baseline.

Line Charts

Line charts often show a trend. Stretching the height of the graph can create fake drama, while stretching the width can underplay it.

Comparing Areas or Volumes

It's harder to compare areas or volumes than lengths. To avoid people getting the wrong impression, use them as a last resort.

Guidelines

Stick to the Point

Avoid Mysteries

A Tale of Two Stories

Unless you're a the third dimer 3D. It skews the comparison.

Actually plotting vision, don't use data and makes ons harder.

Use color to communicate information and not for decoration. Too many colors can confuse and disorient.