The 180 degree rule is a basic guideline for filmmaking that states that two characters or objects in the same scene should always maintain the same left/right relationship between shots. Crossing the imaginary axis that connects the subjects is called crossing the line and results in a reverse angle shot from the opposite side. The rule aims to avoid disorienting viewers but may be intentionally broken by filmmakers for creative reasons, such as in Stanley Kubrick's horror film The Shining.

1. 180 degree
rule
Loran, Hannah & Jacob

2. Definition
The 180 degree rule is a basic
guideline that states that 2
characters in the same scene
should always have the same
left/right relationship to each
other. If the camera passes over
the imaginary axis connecting
the two subjects, it is called
crossing the line. The new shot,
from the opposite side, is known
as a reverse angle.

4. Examples
 In the example of an action scene, such as a
car chase, if a vehicle leaves the right side of
the frame in one shot, it should enter from the
left side of the frame in the next shot. Leaving
from the right and entering from the right will
create a sense of disorientation.
 The rule is not always obeyed. Sometimes a
filmmaker will purposely break the line of
action in order to create disorientation.
Stanley Kubrick was known to do this, an
example being the bathroom scene in The
Shining.