Although Ad-hoc Network-based social utilities only has begun to emerge in recent years，the main field of Application of Ad-hoc Network is not social media. As a burgeoning technological base，it has a wide range of usage. During past forty years，research institutions have conducted adequate research and development projects on Ad-hoc Network at every level. Moreover，the new technology has come into various industrial fields，showing huge potential in Internet of Things，Intelligent Transportation，emergency communication，etc. This article will examine Ad-hoc Network from a macroscopic perspective in aspects of technical principle，technical parameters and social Applications.