Single Glaze -  A simple single piece of glass installed in a window frame

• This is the standard for older homes and many commercial properties.  

Dual Glaze -  Two pieces of glass, separated by an aluminum spacer, and sealed to prevent airflow between the panels 

• California's Title 24 Minimum requirement for replacement windows in Residential properties

Triple Glaze -  Three Pieces of glass configured in a similar manner as Dual glaze 

• Higher energy efficiency, designed for homes in extreme and northern climates, Sometimes used for Sound reduction.