A marble run is a course made for a small ball (or marble) and its aim is to travel from the start to finish with no flaws

To make a marble run you need a small ball and that is it after you make a course using anything you can find

A marble is a small glass ball and is more commonly used for the game 'marbles'

"A toy consisting of a track with bends, obstacles, etc. that marbles can be made to run down."

The Marble League (formerly MarbleLympics and previously Marble Olympics), portrayed as the "Games", has a choreographed Opening and Closing Ceremony, often created using stop motion. Many of the sports are designed to resemble Olympic sports. Each year, the channel uploads a new series of the Marble League, with different events and teams each year, which are introduced in the Qualifying round.