from https://ggplot2-book.org/layers.html#sec-position

• Graphical primitives:
  • geom_blank(): display nothing. Most useful for adjusting axes limits using data.
  • geom_point(): points.
  • geom_path(): paths.
  • geom_ribbon(): ribbons, a path with vertical thickness.
  • geom_segment(): a line segment, specified by start and end position.
  • geom_rect(): rectangles.
  • geom_polygon(): filled polygons.
  • geom_text(): text.
• One variable:
  • Discrete:
    • geom_bar(): display distribution of discrete variable.
  • Continuous:
    • geom_histogram(): bin and count continuous variable, display with bars.
    • geom_density(): smoothed density estimate.
    • geom_dotplot(): stack individual points into a dot plot.
    • geom_freqpoly(): bin and count continuous variable, display with lines.
• Two variables:
  • Both continuous:
    • geom_point(): scatterplot.
    • geom_quantile(): smoothed quantile regression.
    • geom_rug(): marginal rug plots.
    • geom_smooth(): smoothed line of best fit.
    • geom_text(): text labels.
    • Show distribution:
    • geom_bin2d(): bin into rectangles and count.
    • geom_density2d(): smoothed 2d density estimate.
    • geom_hex(): bin into hexagons and count.
  • At least one discrete:
    • geom_count(): count number of point at distinct locations
    • geom_jitter(): randomly jitter overlapping points.
    • One continuous, one discrete:
    • geom_bar(stat = “identity”): a bar chart of precomputed summaries.
    • geom_boxplot(): boxplots.
    • geom_violin(): show density of values in each group.
  • One time, one continuous:
    • geom_area(): area plot.
    • geom_line(): line plot.
    • geom_step(): step plot.
• Display uncertainty:
  • geom_crossbar(): vertical bar with center.
  • geom_errorbar(): error bars.
  • geom_linerange(): vertical line.
  • geom_pointrange(): vertical line with center.
• Spatial:
  • geom_map(): fast version of geom_polygon() for map data.
• Three variables:
  • geom_contour(): contours.
  • geom_tile(): tile the plane with rectangles.
  • geom_raster(): fast version of geom_tile() for equal sized tiles.