Answer:

A hydride is a hydrogen anion. It occurs when hydrogen forms a combination with a less electronegativity element.

When hydrogen reacts with other elements, it generates hydrides.
Ionic hydride is created when hydrogen reacts with group II elements. Examples: KH, LiH, and NaH (NaH)

Molecular hydrides are formed when hydrogen forms a compound with electron-rich elements (P-block elements). Water (H2O) with ammonia (NH3)

Hence, NaH is an ionic hydride (saline hydride), while H2O and B2H6 are covalent hydrides (molecular hydrides). Both B2H6 and H2O are electron deficient molecular hydrides.