Question

What do you mean by:(a)primitive unit cell (b)Non primitive unit cell/ Centered Unit Cells

Answer 1

Answer:

Primitive unit cells contain only one lattice point, which is made up from the lattice points at each of the corners.

                                                      whereas

Non-primitive unit cells contain additional lattice points, either on a face of the unit cell or within the unit cell, and so have more than one lattice point per unit cell.