Idea

is a process in which we extract out of a text, video, or other piece of media an important or (from our own personal perspective) an interesting Concept.

means in any case Exchange with the Environment, but depending on whether one thinks of biological or organic systems or of sense-oriented systems, i.e. of social systems (communication systems) and of mental systems (consciousness and the like), this idea of exchange takes different forms. For biological systems, one thinks primarily of Energy input and output of useless energy; for sense systems, one thinks primarily of exchange of Information.