1. In General, a quantum is a small discrete amount of anything.

2. In Current Science, a quantum is a discrete quantity of electromagnetic energy proportional in magnitude to the frequency of the radiation it represents; an analogous discrete amount of any other physical quantity (as momentum, electric charge).

3. In Neu Theory, the term quantum is used with three primal physical quantities:

- quantum of spin movement/energy (~939 Mev)
- quantum of rise movement energy (~939 Mev)
- quantum of spinrise matter (~1.674 929 351 x 10
^{-27}kg) – made from one quantum of spin movement/energy and one quantum of rise movement/energy that are linked together becoming the quantum whole neutron. The structure of the neutron consists of three invariant elementary matter parts[1a[2a][3a].