A segment is called synchronized (also called in sync) if the voice is heard or the hardsubs appeared simultaneously with the subtitle box. A series of continuous segments is called synchronized if the initial voice of a considered line/dialogue is heard or hardsubs/text appeared where the green line is at the latter half of the gold line.
A segment is considered “late” when the voice of considered line/dialogue (person speaking) is heard or the hardsub appears prior to the subtitle box. If the initial voice is heard before the green line passes the gold line, that is late. If the initial voice is heard when you pause the video at which the green line is on the gold line, that is late.
A voiced segment that contains more than the allowed considered line or dialogue, thus needs to be cut in order for the other lines to be viewed separately. This is to avoid having too many lines appeared on screen once.
A segment that is followed by a space or gap that appears on the screen too quickly to read. The segment will be extend for 2 counts (1.0/1.5 seconds) after the last word is spoken. This allows more time for the viewer to read the subtitles.
These are gaps in between segments that has less than the minimum time ( gap should be at least 2 counts (1.0/1.5 seconds)) allowed in a gap. As a result, a flash or blink effect occurs in between 2 subtitles. For the purpose of reducing the number of segments ‘flashing’ back onto the screen when the gap is too large for the tool to flow from on subtitle to the next.