Abstract: Traffic difficulties have become a general perplexed problem in thedevelopment of large citics, so it is urgent to develop an effective theory oftraffic floty in order to workout a solution of the problem. In this paper, theprogress and up-to-date status of the investigation of traffic flow theory arereviewed in two main aspects, i.e., the dynamical analysis of traffic flow andthe models deseribing junction delays.Various related mathematical and dynamicalmodels are also listed and their validation and limi...