The rule that, to prove the contents of a writing, recording, or photograph,
the original is required unless it is not available for some reason other than
the serious fault of the party trying to prove the contents thereof. If the
original is unavailable, the testimony of the person who created the original
or the person who read it (if a writing), listened to it (if a recording), or
saw it (if a photograph) may testify to its content. However, modern
evidentiary rules usually permit the use of mechanical, electronic, or other
similar copy instead of the original.