Bravais

Identification of directions, and planes, in a crystal lattice:
Graphical illustration of the Miller indices scheme

Bragg

Reflections of waves (X-ray, free electrons as plane waves, etc)
in a periodical structure (e.g. crystal lattice)

Bloch

Energy band structure and wavefunctions of periodically modulated waves,
such as electrons in a crystal lattice

Fermi

 Concentrations of electrons and holes in a semiconductor
with different band gap energies and doping levels, at different temperatures