What Does Parallax Scrolling Mean?
Parallax scrolling is a scrolling technique used in computer graphics in which background images move more slowly than images in the foreground, creating the illusion of depth and immersion. It is often used in video games.
Techopedia Explains Parallax Scrolling
The word “parallax” is taken from astronomy and defined as the apparent displacement or the difference in apparent direction of something when viewed from two different vantage points.