Combining precise microscopic measurement with quantitative image analysis, video microscopy has become an important, real space experiment technique to study the microscopic properties of soft matter systems. On the one hand, it provides a basic tool to observe and record the microscopic world. On the other hand, it offers a essential experiment method to study the underlying physics of the microscopic world. This paper reviews the development of the video microscopy, introduces the corresponding hardware and video processing software, and summarizes the typical applications, and recent progresses of video microscopy in colloidal suspensions. The future of the video microscopy in the soft condensed matter physics and interdisciplinary research is discussed.