The best we can do is, roughly speaking, is to
say that when there are only a few sources, say two interfering
sources, then the result is usually called interference, but if there
is a large number of them, it seems that the word diffraction is
more often used In the double-slit experiment, we must note that the pattern on the
screen is actually a superposition of single-slit diffraction from each slit
or hole, and the double-slit interference pattern 10 6