Also known as an Instance Chart, Strip Plot, Stripe Plot.

Not to be confused with the very similar Warming Stripes visualisation.

A Barcode Plot is a chart used to visualise the data distribution across multiple categories by plotting short stripes along an axis. Each stripe can represent a single data point or a count.

There are two main kind of Barcode Plot: first, the kind that plots a series of “barcodes” to compare the distributions between various categories across a single dimension. The other kind is an “Instance Chart” that plots stripes along a time axis to show the occurrence of various categories over time.

Barcode Plots can be displayed either horizontally or vertically. Typically, the stripes are a single colour, but colour coding can be used to distinguish categories apart. To help make overlapping values visible, the opacity of the stripes can be reduced, which can help to reveal where the data distribution is concentrated.