Terminology
Block
A block is an orthogonal clump of units (i.e. a line segment, rectangle, cuboid, hyper... you get the idea) and so can be easily defined by 2 opposite ends/corners in any dimension.
BlockSet
A blockset is a disjoint set of blocks that resolves any layout of units in a concise and consistent manner.
Normalising
A layout of units can be described in a multitude of ways using blocks in an additive and subtractive manner.
Normalising, is the process of mapping that state to a set of disjoint blocks in a consistent fashion such that matching layouts are always resolved to the same set of blocks regardless of how they were constructed.
Unit
A single amount of space in any dimension (i.e. 1x1 square, 1x1x1 cube)