Questions on legends, figures (usually insets) that indicate what those lines/bars/points in plots refer to, using arrangements of graphic elements and text, whether manually or using built-in functions.

Mathematica provides built-in Legend functionality for charting functions such as BarChart and PieChart. For plotting functions such as Plot, ListPlot and DateListPlot, the PlotLegends` package is available. However it is slow and difficult to customise. The ShowLegend function provided by that package offers a little more control. Generally, however, both performance and aesthetics are better if one uses a custom function such as this one.

Please consider using one of the tags or according to whether your question is about 2D or 3D graphics.

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