This paper provides a comprehensive survey of Augmented Reality (AR), a technology that integrates 3-D virtual objects into the real world in real time. The author, Ronald T. Azuma, from Hughes Research Laboratories, describes various applications of AR, including medical visualization, manufacturing and repair, annotation, robot path planning, entertainment, and military aircraft navigation. The paper discusses the characteristics of AR systems, focusing on the trade-offs between optical and video blending approaches, and addresses the significant challenges of registration and sensing errors. It also explores future directions and areas requiring further research. The survey aims to provide a starting point for anyone interested in researching or using AR, offering a detailed overview of the current state-of-the-art and potential future developments.This paper provides a comprehensive survey of Augmented Reality (AR), a technology that integrates 3-D virtual objects into the real world in real time. The author, Ronald T. Azuma, from Hughes Research Laboratories, describes various applications of AR, including medical visualization, manufacturing and repair, annotation, robot path planning, entertainment, and military aircraft navigation. The paper discusses the characteristics of AR systems, focusing on the trade-offs between optical and video blending approaches, and addresses the significant challenges of registration and sensing errors. It also explores future directions and areas requiring further research. The survey aims to provide a starting point for anyone interested in researching or using AR, offering a detailed overview of the current state-of-the-art and potential future developments.