Chart Parts
The parts every chart composes: axes and ticks, legends, tooltips, annotations, brushes, labels and editorial marks.
A few categories, compared
Declarative annotations: text notes, ranges, reference lines and row notes in data units.
The x and y axes every chart composes: tick placement, number and date formats, units, gridlines and the compact narrow-width form.
A drag-to-select range control under a chart that zooms the plot above to the brushed window.
Series key with label, value and an optional progress bar; pattern-aware under decoration.
SVG text that punches a plot-ground halo out from behind itself, so a label stays readable directly ON a mark instead of beside it.
Series and value labels on a chart: end labels, key labels and the collision layout that keeps every label readable or restates it for assistive technology.
The colour-scale key for a sequential or diverging chart: a continuous ramp with its low and high values.
The radius key for an area encoding (a scatter sizeKey, a bubble cluster): three sqrt-scaled sample circles, matching every area mark's areaRadius() honesty rule.