This page keeps the most useful pointers from the older “class 2” plotting notes: built-in demo material, margin and axis tricks, widget examples, and irregular surface plotting.
If you have not already done so, skim the introduction and the setup page first.
The fastest way to browse IDL’s own plotting examples is still:
IDL> demo
That gives you direct examples for graphics, image processing, widgets, and maps.
The older notes emphasized a few recurring tools: !P.POSITION, legends built with
XYOUTS and PLOTS, and right-side axes using AXIS, YAXIS=1.
PLOT, y1, XTITLE='Time', YTITLE='Signal 1'
OPLOT, y2, COLOR=100
AXIS, YAXIS=1, YRANGE=[0, 50], YTITLE='Signal 2', COLOR=100
The original legend demonstration image is preserved below.

The PPPL mdsw.pro widget remains a useful large example for draw widgets, menus, event
handling, and plotting against MDSplus data.

The older class notes also pointed at stacked plots and irregular-surface rendering.

