Insulated glass, also known as double-glazed or thermal glass, consists of two or more glass panes separated by a spacer and sealed to create an insulating air or gas-filled space between them. This design reduces heat transfer, enhances energy efficiency, and minimizes condensation and noise. The space between the panes is often filled with inert gases like argon or krypton to improve thermal insulation. Insulated glass is commonly used in windows, doors, and curtain walls in residential and commercial buildings to enhance comfort and reduce energy costs.