A plot references every measurement. Changing a measurement's parameters will affect all plots showing the measurement, but creating multiple plots allows you to simultaneously manage different displays of the same results. To demonstrate this, begin by creating a model and running a simulation on it. Then:
Create two plots. Notice that both of the plots reference both of the measurements.
In one of the plots, change the chart type. Toggle off the visibility of one of the measurements.
Choose your other plot. Notice that in this view the chart type has not changed and both measurements are visible.
On the View ribbon in the Views group, from the Tile menu, choose one of the multiple tilings. You should now see both of your plot views.
A more extensive discussion of measurements and plots, with a worked-out example, is available here.