Here's why:

* Ionic Bonding: Sodium chloride is formed by ionic bonds between positively charged sodium ions (Na+) and negatively charged chloride ions (Cl-). These strong electrostatic attractions hold the ions together in a rigid, crystalline structure.

* High Melting Point: The strong bonds require a lot of energy to break, resulting in a high melting point of 801°C (1474°F).

* Room Temperature: At normal temperatures, sodium chloride maintains its solid structure.