* Hydrogen Fluoride (HF): This is a colorless gas that dissolves in water to form hydrofluoric acid, a highly corrosive acid used in etching glass and manufacturing semiconductors.

* Sodium Fluoride (NaF): This is a white, crystalline salt commonly used in toothpaste to prevent tooth decay, as a pesticide, and in water fluoridation.

Fluorine is extremely reactive and forms compounds with most other elements. There are many other compounds that fluorine can form, but these two are common and important examples.