Continuity!
Just what is
continuity?
Continuity deals
with the state of a video scene or film, and whether a set of events
depicted within it are unbroken by sudden, jarring changes that occur
from shot to shot.
These changes could
be as simple as a props/actors changing location from one shot to the
next; colthing being different without any obvious explanation; a
prop changing in appearance (a TV suddenly turns on without action of
those in the shot).
A more obvious
continuity glitch would be a noticeable change in lighting in a short
scene, that happens with no explanation. This is why many shots are
filmed at a particular location all at once, and not broken up, in
order to preserve continuity as best as possible.
Another continuity
error would be when an actor leaves a room by a door/opening in one
shot, and reappears in the next shot on the wrong side of the next
location. For example, if the actor leaves by the right, he should
reappear on the left in the next shot, and vice-versa. If they exited
a door by the same side after the cut to next shot, it would appear
strange, especially if the next location was too similar to the
former.