Editing establishes the structure and content of the production along with the production’s overall mood, intensity, and tempo.
Word Juxtaposition means an act or instance of placing something close together or side by side, especially for comparison or contrast.
JUXTAPOSITION: The arrangement of two or more ideas, characters, actions, settings, phrases, or words side-by-side or in similar narrative moments for the purpose of comparison, contrast, rhetorical effect, suspense, or character development.
In Soviet filmmaking of the 1920s, “montage” was a method of juxtaposing shots to derive new meaning that did not exist in either shot alone.
Juxtaposition is not only used with images but also with sound. For example, narrative story and shots of interviewee and objects/people he is talking about.
Another good example of it is a travel video made for STA Travel Australia (https://www.youtube.com/watch?v=-BrDlrytgm8). It shows one guys constantly walking ahead but every second the background changes to show places that he has been such as different countries and cities.
PARALLEL EDITING (cross cutting) is the technique of continuously alternating two or more scenes that often happen simultaneously but in different location. For example, outdoes ad inside one building.
Parallel editing is used to add interest and excitement to an otherwise boring sequence.
Often in parallel editing, the two ‘parallel scenes’ intersect and culminate in climax. It is also used to mislead the viewer.