The continuity system is a highly standardised system of editing , that was originally associated with Hollywood film but is now virtually universal in commercial film and television . The continuity system helps link shot from shot to keep a clear narrative to what is happening in the shots.

180 degree rule
This rule helps to ensure that with the movement of the shot the subject stays in the same direction no matter what way you look at it. The 180 degree line is a line that must not be crossed while shooting
, the camera must stay on one side of the line throughout the entire scene because even if the scene is shot only partly over the line the entire scene will flip positions of a character or object.

Shot reverse shot is a technique where one character is shown looking at another character , then the other character is shown looking back at the first character. The characters are shown facing opposite directions, it gives the viewer the effect that they are  where one character is shown looking at another character, and then the other character is shown looking back at the first character. Since the characters are shown facing in opposite directions, the viewer assumes that they are looking eachother implying communication in some form is about to take place. 

Establishing/ re- establishing Shot
An establishing shot is almost like a set up it creates context for the scene by showing a relationship between its characters and objects. Typically is a white shot and is used to open a scene. The re-establishing shot goes back to the establishing spot to establish the context of the scene. 

Eye-line match cut (POV)
An eye-line match cut helps us as a viewer to see what the character is seeing. The shot will start off as following the character the cut to whatever the character is viewing so it’s as if the audience are uncovering what the actor did also.