Book excerpt: Seminar paper from the year 2014 in the subject Engineering - Artificial Intelligence, grade: 8.8345, course: B.Tech. Information Technology, language: English, abstract: Understanding human activity and behavior, especially real-time understanding of human activity and behavior in video streams is presently one of the most active areas of research in Computer Vision and Artificial Intelligence. Its purpose is to automatically detect, track and describe human activities in a sequence of image frames. Challenges in this topic of research are numerous and sometimes very difficult to work out. This paper presents a brief review over the overall process of Human Activity and Behavior Recognition both real time and non-real time, and some of the applications present in current world. The main purpose of this survey is to extensively identify some of the existing methods, critically analyze it and acknowledge the work done by researchers in this field so far.