Data Visualization Glossary

A chart similar to a line chart but with the area below the line filled in, used to show cumulative totals or proportions over time.

A reference line in a chart that provides a scale for measuring and locating data values, typically horizontal (x-axis) and vertical (y-axis).

An interactive technique allowing users to select a subset of data in one view, typically by clicking and dragging, to highlight corresponding elements.

A visual property of a mark (such as position, color, size, or shape) used to encode a data attribute.

Unnecessary decorative elements in a graphic that do not convey data information.

A thematic map where geographic regions are shaded proportionally to a data variable.

Designing visualizations that remain readable for people with color vision deficiencies, using colorblind-safe palettes and redundant encoding.

A visual display of key metrics and data points consolidated on a single screen, designed for at-a-glance monitoring.

The proportion of a graphic's total ink that is used to represent data, as opposed to non-data elements.

A color scale using two contrasting hues meeting at a meaningful midpoint, used for data with a natural center.

The mapping of data attributes to visual properties such as position, color, size, and shape.

Splitting data into subsets and displaying each subset in its own panel, also known as small multiples or trellis plots.

Perceptual laws describing how humans group visual elements, including proximity, similarity, enclosure, and continuity.

A framework decomposing charts into layered components: data, aesthetics, geometry, statistics, coordinates, and facets.

A visualization using color intensity in a matrix layout to represent the magnitude of values across two categorical dimensions.

A visual communication piece combining charts, text, icons, and illustrations to present information in an engaging, narrative format.

A key that explains the encoding used in a visualization, mapping visual properties back to data values or categories.

A measure of how much a graphic distorts the underlying data, calculated as the ratio of visual effect size to data effect size.

A geometric primitive (point, line, area) used to represent a data item in a visualization.

A visual property processed rapidly and unconsciously, enabling instant detection without focused attention.

A flow diagram where the width of arrows is proportional to the quantity of flow, used to show transfers or transformations between stages.

A chart using dots to represent the values of two quantitative variables, with position on the x and y axes showing the relationship.

A small, inline graphic that shows a data trend without axes or labels, typically embedded in text or tables.

A small information popup that appears when hovering over a data element in an interactive visualization.

A space-filling chart using nested rectangles to represent hierarchical data, with area proportional to a quantitative value.