William Stephen George Mann is a Canadian engineer, professor, and inventor who works in augmented reality, computational photography, particularly wearable computing, and high-dynamic-range imaging. Mann is sometimes labeled the "Father of Wearable Computing" for early inventions and continuing contributions to the field. He cofounded InteraXon, makers of the Muse brain-sensing headband, and is also a founding member of the IEEE Council on Extended Intelligence (CXI). Mann is currently CTO and cofounder at Blueberry X Technologies and Chairman of MannLab. Mann was born in Canada, and currently lives in Toronto, Canada, with his wife and two children. In 2023, Mann unsuccessfully ran for mayor of Toronto.

Augmented reality (AR) is an interactive experience that combines the real world and computer-generated 3D content. The content can span multiple sensory modalities, including visual, auditory, haptic, somatosensory and olfactory. AR can be defined as a system that incorporates three basic features: a combination of real and virtual worlds, real-time interaction, and accurate 3D registration of virtual and real objects. The overlaid sensory information can be constructive, or destructive. As such, it is one of the key technologies in the reality-virtuality continuum.