cal-heatmap is a JavaScript visualization library used to render time-series data as a grid of colored cells. It functions as a customizable calendar component that maps data density and frequency over temporal intervals ranging from minutes to years.
The library provides built-in support for localized temporal displays, allowing for the adjustment of regional date formats, timezones, and locale-specific week starts. It utilizes a plugin system for both the calendar layout and heatmap charts to extend behaviors and visual styles.
The system manages data visualization through SVG-based grid rendering and includes capabilities for calendar date navigation and layout configuration. It also supports data-driven color mapping to translate numerical values into visual density patterns.