Image for "Basic plots - plot" should hint at markers

Currently the image is just sine line, which could trick users in thinking that plot is for lines and scatter is for markers.

I propose to additionally show another set of values with markers, e.g. something like:

[jklymak]

as general case plot is for lines and scatter is for points.

scatter is for when you need a third dimension, either represented as marker size or color. Otherwise, you should just use plot.

[timhoffm]

for smaller datasets the difference is negligible & so you may as well not overload a function with two semantically distinct

I argue the other way round: From the data semantics:

• plot() is primarily for functional relationship y = f(x) so that there is only one y per x. Whether you draw this with single markers or lines or both is a stylistic choice.
• scatter() is for drawing points in the (x, y) plane, and optionally adding additional information like color and size.