Shot/Reverse Shot

Shot reverse shot (or shot/countershot) is a film technique where one character is shown looking at another character (often off-screen), 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 at each other.
(Source: http://en.wikipedia.org/wiki/Shot_reverse_shot)

http://www.youtube.com/watch?v=3cXqlg85-VY

Match on Action

A match on action is a cut that connects two different views of the same action at the same moment in the movement, it would take place int he middle of an action.

http://www.youtube.com/watch?v=sbVS-O6zYJc
In this video link of blade it shows a match on action shot when blade comes into the scene.

180 degree rule

The 180° rule is a basic guideline in film making that states that two characters (or other elements) 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. (source: http://en.wikipedia.org/wiki/180_degree_rule). 

http://www.youtube.com/watch?v=oNOT9iHDSXU