A side-scroller is a well-known game principle (like in Super Mario or Sonic) where you have to navigate your character through a world with obstacles.
This game is often used in campaigns to promote new products. In the side-scroller, the character must navigate through an environment (such as a city, construction site, or forest) by running, flying, or surfing without failing. Along the way, your character can score extra points by grabbing and collecting items.