Histogram
A graph showing the distribution of brightness values in an image, from shadows (left) to highlights (right).
Histograms provide an objective view of image exposure that is more reliable than visual assessment on a screen. A well-exposed image typically shows a spread across the full range without clipping at either end. Peaks on the left indicate shadow-heavy images; peaks on the right indicate highlight-heavy images. Photographers and editors use histograms to evaluate and guide exposure adjustments.