Privacy glass is a type of glass that can change its transparency when an electrical current is applied. This technology allows the glass to switch from clear to opaque, providing privacy on demand. It is commonly used in offices, homes, and vehicles to create private spaces without the need for curtains or blinds. The glass works through a process called electrochromism, where the application of electricity alters the arrangement of molecules within the glass. This feature not only enhances privacy but also helps in controlling light and heat, making it an energy-efficient option for modern architecture and design.