Cogliati et al. presented the hypertextbook, web-based teaching and learning resource, which integrate various types of multimedia resources such as text, picture, sound, illustrations, slide shows, video clips, and active learning models on topics of the theory of computing. They emphasized the active learning models which allows learners to actively engage the algorithm materials. It is integrated seamlessly into a hypertextbook at arbitrary steps of an algorithm to illustrate a concept, and students who encounter the them are required to interact with the models. In the different cases, students should provide input for the finite state machine, or construct proper solutions for given exercises. The active learning models consist of 5 different variantions: a passive learning example, active learning example, active learning exercise, authoring, and a standalone application. (By Haeyong Chung)