The adoption of educational technologies such as e-textbook has offered a new opportunity to gain insight into teachers' usage of ICT (Information and Communication Technologies). In the e-textbook platform, customized digital products and the learning activities organized in digital environment require teachers to make greater efforts in planning lessons and producing resources. In addition, usage of technology can vary greatly from one group of teachers from another in various contexts. In this study, we demonstrate how computations like event segmentation and contextual numbers can be exploited in visualizing trajectories of teacher's ICT usage. We also study with the experience structure via the implicit patterns within the raw data of an e-textbook platform. Such automated visual characterization might be helpful to the wide and scalable application of teaching analytics to represent teacher's ICT usage. [For the full proceedings, see ED596512.]