What is the term for a compound made for only two elements?

Ammonia: NH3

Calcium carbonate: CaCO3

Sand: SiO2

Salt: NaCl

Water: H2O

Carbon dioxide: CO2

Carbon monoxide: CO

Hydrolic Acid: HCl

Nitrous oxide: N2O

Silver Ioide: AgI

Potassium chloride: KCl

Aluminum nitride: Aln

Boron carbide: B4C

Cadium Telluride: CdTe

Cesium Flouride: CsF