Flow is a really interesting concept that has a close relationship to human happiness. It is the experience you have when you are fully and completely absorbed in an activity and nothing else seems to matter. You lose all sense of time and your concentration is so intense that there is no attention left over to think about anything else. You feel focused, productive, and deeply satisfied. It is actually the root of creativity and productivity, and it is strongly associated with happiness. Flow is the optimal state that results from an profound engagement with an activity you enjoy, the time you feel that you are in the zone or in the flow. It is the opposite of the distracted mind-wandering.
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