Object slot

An object slot is a location in memory that may or may not contain an object. There are 240 object slots that may either be occupied or unoccupied. The slots that are occupied by objects are stored first, and the slots that are unoccupied (empty) are stored second. If all the object slots are filled up and an object tries to load, the game will crash, unless the object is an unimportant object such as a dust particle.

Effect of Cloning

Main article: Cloning

Cloning occurs when Mario holds an empty object slot.