to set your IDL current directory to wherever you are:
   IDL> cd, 'D:\rahn\EyeDeeEl\coyote'   or whatever
   IDL> cd, current=currentdirectory
   IDL> print, currentdirectory

to bring a graphics window forward (window 0 (the default) in
this case:
   IDL> wshow, 0

to put multiple plots in the same window, use /noerase in
all subsequent commands (else display will be erased first
before each command is executed, except TV and TVSCL)

IDL> curve = loaddata(1)
     time = findgen(101) * (6.0/100)index = indgen(20)*5
     peak = loaddata(2)
     lat = findgen(41) * (24.0/40) + 24
     lon = findgen(41) * (50.0/40) - 122
     image = loaddata(7)

Polyfill will color the interior of a polygon

To set shape of window:
   IDL> window, xsize=600, ysize=400 
   sets window half again wider than tall

color is TrueColor and 24 bit: i.e., static color and RGB color model

to plot a string:
   xyouts, 50, 50, 'some string', /device
      /device causes pixels to be used as coordinates, /normal causes coords to go
         0.0 to 1.0 in each direction, default is data coords
      color=1  for white (default)

Use PLOTS to draw lines (including several segments) and symbols