Flow is the affective state of optimal experience that creates pleasure by balancing the challenge of the task at hand to the skills of the person. Originally discovered and popularized  by Mihaly Csikszentmihalyi ("chick-sent-me-high-ee"), flow has been studied across diverse tasks ranging from athletics to learning by students to games. More recently, flow has been used as an affective state of students using ITS systems.
Foundations of Flow
Flow, as originally formulated by Csikszentmihalyi and described in his book , has 8 components that are highly associated with being in the state of flow:
1. A challenging activity that requires skill
Flow in ITS Systems
Flow over time in ITS Systems
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