Documentation Link

https://matplotlib.org/devdocs/api/_as_gen/matplotlib.axes.Axes.legend.html#matplotlib.axes.Axes.legend

Problem

Inspired by #26612

3. Legends: Replace confusing terminology like bbox_to_anchor etc, and make the legend positioning simpler

Suggested improvement

Parameter loc

• Explicitly state that the locations are positions within a given box (configurable via bbox_to_anchor, default: Axes box)

• Replace

  The strings 'upper left', 'upper right', 'lower left', 'lower right' place the legend at the corresponding corner of the axes.
  The strings 'upper center', 'lower center', 'center left', 'center right' place the legend at the center of the corresponding edge of the axes.
  The string 'center' places the legend at the center of the axes.

  By Add a visual similar to the cheat sheet
  
  but with the string names in the respective positions.

Parameter bbox_to_anchor

• Make it more clear that this is an advanced option for free placement
• Link to https://matplotlib.org/devdocs/users/explain/axes/legend_guide.html#legend-location
• Link to https://matplotlib.org/devdocs/api/figure_api.html#matplotlib.figure.Figure.legend for outside legend (which in former times could only be achieved using bbox_to_anchor), and there make the outside options more prominent.