Normal Pocket Dimension

A Normal pocket Dimension / Reality is a small reality space with extremely varying size and dimensionality, ranging from around a femtometer to a couple million lightyears at the very extremes.

The difference between a Normal and Special pocket dimension is pretty complex, so here is a graph of all the details and differences: There has even been an organisation which's purpose is to allow people access of a pocket dimension, in what is known as the Small Pocket Dimension Complex, containing a grid of Normal pocket dimensions each 1 kilometer wide.