The 180 rule:

In film making. the 180-degree rule is a basic guideline regarding the on-screen relationship between a character and another character or object within a scene. The 180 degree rule is essential in keeping the viewer focused and avoiding confusion.

Once a scene has been established, the camera must stay on one side of the action. If two people are facing each other, a line must be drawn. This line usually runs straight down the middle between the two people. Once this line is in place, the camera can move anywhere providing it stays on the same side of the line once filming has begun. If the camera is switching between two faces during a conversation for example and then suddenly cuts to the other side of the line, then it will appear that both people are facing the same direction instead of looking at each other.

The 30 degrees rule

This is a basic film editing guideline.  That says the camera must moves 30 degrees between shots.   If this rule isn't followed a jump cut occurs and there is a risk that the audience starts focusing on the filming technique instead of the story that is being narrated.

Match on action

https://www.youtube.com/watch?v=kIGz3igGpMk

This is a clever way of editing action shots to intrigue the audience.  The editor cuts from one shot to another view that matches the first shot's action. Although the two shots may have actually been shot hours apart from each other, cutting on action gives the impression of continuous time when watching the edited film. This is a simple thing to do but is so effective and is very important that this is done properly.  If this is not done correctly the whole shot will look tacky and very noticeable to the audience watching.