Heatmap

Uses color intensity across a matrix to reveal patterns and concentration.

What question it answers

Where is intensity concentrated across two categorical dimensions?

Where to use it

Matrices comparing intensity across two dimensions such as weekday × hour or feature × segment.

When to use it

Use it when a matrix contains enough repeated cells that color intensity helps reveal concentration and pattern.

When not to use it

Avoid it when users need exact cell values at a glance or when color differences are too subtle to decode reliably.

Responsive design

Keep row and column labels readable, allow controlled scrolling for large matrices, and preserve the intensity legend near the grid.

Arabic and RTL

Use RTL row/column labels where linguistic, but do not arbitrarily reverse ordered time or numeric dimensions in the matrix.

Anatomy

Chart context: Names what each cell counts (tickets per hour) and the period, so intensity has a unit.
Cells: Colour lightness encodes the value of each weekday × hour combination. Patterns appear as bands and clusters.
Column dimension: One categorical or ordered dimension (hours). Keep the order meaningful and labels readable.
Row dimension: The second dimension (weekdays). Sorting rows can reveal structure that a fixed order hides.
Intensity scale: Maps colour to numbers. Use one light-to-dark hue and place the scale next to the grid.

Accessibility

Provide numeric values on focus/tap and an alternative table; use a palette with sufficient perceptual contrast.

All lessons

Bar Chart — Compares values across categories using length on a common scale.
Line Chart — Shows change across an ordered sequence, most often time.
Area Chart — Emphasizes magnitude over an ordered sequence by filling the area under a line.
Pie / Donut Chart — Shows a small number of parts that make up one meaningful whole.
Scatter Plot — Reveals relationships, clusters and outliers between two numeric variables.
Histogram — Shows the distribution of a numeric variable across value ranges.
Box Plot — Summarizes distribution, median, spread and potential outliers compactly.
Heatmap — Uses color intensity across a matrix to reveal patterns and concentration.
Treemap — Shows hierarchical part-to-whole relationships through nested rectangles.
Funnel Chart — Shows how a population changes through ordered stages of a process.
Waterfall Chart — Explains how positive and negative contributions produce a final total.
Sparkline — Shows a compact trend without the full framing of a standard chart.
Gauge — Shows one value within a bounded range when position against a threshold matters.
Combo Chart — Combines compatible visual marks when two related measures need coordinated comparison.
Geographic Data Map — Maps values to locations or regions when geography is part of the question.
KPI / Stat Card — Presents one important metric with enough context to judge its current value and change.
Data Table — Presents structured records in rows and columns, with table-level search, filtering, sorting, selection and pagination treated as parts of the whole component.
Dashboard Card / Panel — Groups one coherent dashboard task, metric or visualization into a bounded region with clear hierarchy.
Filter Bar — Places the most important scope controls close to the data they affect.
Filter Panel — Collects a larger set of filtering controls in a dedicated surface.
Date Picker / Date Range Picker — Lets users choose one date or a bounded time range for reports, filters and analytics.
Sidebar Navigation — Provides persistent access to major dashboard destinations and groups.
Top App Bar — Holds page identity, global actions and high-priority controls at the top of an application.
Breadcrumbs — Shows hierarchy and provides a path back through nested dashboard levels.
Tabs — Switches between peer views inside the same dashboard context.
Alert / Banner — Communicates important contextual or page-wide information that should remain visible until understood or resolved.
Toast — Confirms a brief asynchronous outcome without blocking the current task.
Notification Center — Collects system and workflow updates that users may need to revisit.
Dropdown / Overflow Menu — Moves lower-priority or contextual actions into an on-demand menu.
Modal / Dialog — Creates a focused temporary task that may block interaction with the underlying dashboard.
Drawer / Side Panel — Opens contextual controls or details from an edge while preserving the page behind it.