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Could somebody explain the difference between Subjective Idealism and Absolute Idealism

Hi all, I've particularly been reading about various schools of Indian philosophy (Advaita Vedanta, Shunyavada, Kashmir Shaivism, and Vijnanavada, to be specific) and I've found many references to schools of Western philosophy to which they are compared. While I do have interest in Western philosophy as well, I'm kinda tripped up over the distinctions they make between the schools of Subjective Idealism (which I have heard is associated with the likes of Berkeley) and Absolute Idealism (which, if I'm not wrong, is Hegel's philosophy). If interested, feel free to comment on their connections with Eastern philosophy as a whole.
gpt
Like most -ism words, "idealism" means a lot of different things to different people. Most western philosophers will associate it with Berkeley-style idealism. By reputation at least, this is the view that what we experience is purely mental, not anything real that exists independent of the minds of those who experience it. 

The other two famous idealisms, (Kant's) transcendental and (Hegel's) absolute idealism, have nothing to do with this, and are explicitly opposed to it. For Kant, the word "ideal" doesn't mean "fake" or "purely mental", it means something closer to how the word is used in ordinary english today: the ideal is a standard or goal that you strive for, which striving organizes your activity and gives it sense. Kant argued that many important metaphysical concepts were not concepts of objects, but were ideals in something like this sense. We never have knowledge of traditional philosophical objects like the universe as a whole or the nature of the good, but instead those concepts serve as ideals, and our unending striving to get closer to knowledge of them is that in light of which the rest of our knowledge makes sense, even if we can never actually get there.

Hegel accepts this basic structure but argues that it's wrong to think we never get to knowledge of those ideals. On the contrary, self-consciousness itself *is* knowledge of those ideals; we cannot help but know them insofar as we know anything at all. The best contemporary articulation of a view like this is Sebastian Rodl's *Self-Consciousness and Objectivity*.