Windows Aero

Windows Aero (a backronym for Authentic, Energetic, Reflective, and Open) is the design language introduced in the Microsoft Windows Vista operating system. The changes introduced by Windows Aero encompassed many elements of the Windows interface, with the introduction of a new visual style with an emphasis on animation, glass, and translucency; interface guidelines for phrasing and tone of instructions and other text in applications were available. New cursors and sounds based on Windows Aero design principles were also introduced.

Windows Aero was used as the design language of Windows Vista and Windows 7. The flat design-based Metro design language was introduced on Windows 8, although aspects of the design and features promoted as part of Aero on Windows Vista and 7 have been retained in later versions of Windows (barring design changes to comply with Metro or Fluent).