180 Degree Rule

180 Degree Rule:
 In film making, the 180-degree rule is a basic guideline regarding the on-screen spatial relationship between a character and another character or object within a scene. An imaginary line called the axis connects the characters and by keeping the camera on one side of this axis for every shot in the scene, the first character will always be frame right of the second character, who is then always frame left of the first. If the camera passes over the axis, it is called jumping the line or crossing the line. Cutting the line can result to confusion in the audience, and they may lose concentration. so therefore the rules of the 180 degree rule should be followed!

This picture shows the axis between two characters and the 180° arc on which cameras may be positioned. When cutting from the arc, the characters switch places on the screen.