Unit

All floating-point numbers in the game's code that represent sizes or distances represent them using the same scale, and the distance represented by a value of 1 on this scale is known as a unit. A unit is equal to roughly 0.7% of Mario's height, but despite being extremely small, units are not the smallest meaningful distance in the game's engine since distances in units are represented using floating-point numbers rather than integers.

Although it is impossible to see any unit-based values in an unmodified version of the game, various mods created for the purposes of glitch hunting allow viewing variables such as Mario's coordinates, which are by definition represented in units.