Solid

Solid is one of the three classical states of matter .
 It is characterized by structural rigidity and resistance to changes of shape or volume. Unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire volume available to it like a gas does. The atoms in a solid are tightly bound to each other, either in a regular geometric lattice. 

Microscopic description

The atoms, molecules or ions which make up a solid may be arranged in an orderly repeating pattern. 

the movement of particles are in to and fro movement. 

 Almost all common metals, and many ceramics, are polycrystalline.

  These solids are known as amorphous solids; examples include polystyrene glass. and

Whether a solid is crystalline or amorphous depends on the material involved, and the conditions in which it was formed.

 Solids which are formed by slow cooling will tend to be crystalline, while solids which are frozen rapidly are more likely to be amorphous. 

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