Solids

1. Volume and Shape

1.1. Definite shape

1.2. Definite volume

1.3. The volume and density do not change easily

1.3.1. Turn to liquid at melting point

2. Atoms in solids

2.1. Vibrate in place

2.1.1. Materials

2.1.2. Personel

2.1.3. Services

2.1.4. Duration

2.2. Low energy level

2.3. The atoms are in fixed positions