A network solid is a substance in which all the atoms are covalently bonded to each other forming a large network structure.
Covalent Network Crystal: A crystal in which all atoms are interconnected by covalent bonds forming an extended network throughout the crystal.
Diamond Structure: An example of network solid where carbon atoms are linked by covalent bonds in tetrahedral arrangement giving it extreme hardness.
Silicon Dioxide (SiO2): Another example of network solid commonly known as quartz or sand.