Each agent acts based on behavior rules, and the internal state is modified by the communications among agents. We examines the case study of the competition on the standard of Video Tape Recorder (VTR). In this case the compatibility of the video software is definitely important to choose the VTR. The study of conventional economics is insufficient at dealing with emergent st ructure caused by interactions among agents. The simulation result shows that our model is useful to understand what has happened in the technological lock-in phenomena. The communications among agents are breaking symmetry of the market share, then the asymmetry is enlarged further with accelerated speed.