Heatmap
A heatmap is a data visualization technique that uses color gradients to represent the magnitude of values in a matrix or dataset, making patterns, trends, and outliers easily discernible. It is commonly applied in fields like data analysis, user experience research, and scientific computing to display correlations, densities, or frequencies across two dimensions. By mapping numerical values to a color scale (e.g., from cool to warm colors), heatmaps provide an intuitive, visual summary of complex data.
Developers should learn and use heatmaps when analyzing large datasets to identify hotspots, clusters, or anomalies, such as in website analytics to track user clicks, in machine learning for feature correlation matrices, or in genomics for gene expression patterns. They are essential for creating interactive dashboards, enhancing data-driven decision-making, and communicating insights effectively to non-technical stakeholders through visual tools like libraries in Python or JavaScript.