I'm curious about the principle of video editing. When the video is edited on a certain NLE software, how does the computer display the edited result to the user on the preview screen? Does it create a temporal video file on the disk to store the edited result or just store the edited video stream in the memory?
[Ivan Gao]"Does it create a temporal video file on the disk to store the edited result or just store the edited video stream in the memory?"
I don't believe it does either by default. When you playback the edited result the computer is playing back directly from the files stored on hard drive(s). Although you can 'render' the entire timeline and it will write a new video file to disk, and some NLEs will allow to to do a RAM preview (which writes the data to RAM) but it's usually not very long (only a matter of seconds) because of the file sizes videos create.