There are two types of solids:
Crystalline solids
Solids with a definite geometric pattern.
Examples: Iron, copper, silver, sulphur etc. are some elements which form crystalline solids. Potassium chloride, sodium nitrate etc are some of the compounds, which are crystalline.Amorphous solids
Solids with particles not arranged in a regular fashion. They have only short range order or even the particles are disordered in some cases.
