A voxel is an element of a 3D grid. Depending on the representation, it can store occupancy, density, distance, color, learned features, or other attributes.

Domain
3D grid
Can store
Occupancy, fields, or features
Sparse grid
Stores active cells
Not equal to
A polygon

Dense and sparse grids

Dense grids allocate every cell in a volume. Sparse structures store active regions, which is important because most of the volume around a surface is empty.

Interpret cubic resolution carefully

A label such as 1024³ describes a three-dimensional resolution setting. It does not mean the exported mesh contains that many vertices or the texture is 1024 pixels wide.