The Most Important Works In Science Fiction

Not sure if you could call 1984 sci-fi.
The overarching term, for purists, is speculative fiction.

SpecFic makes some changes to the world that distinguish it from ours, and then runs it through its paces to see the outcome.

In Sci-Fi, those changes are often technological in source.

affected me more than any other book I've ever read. A kind of loss of innocence (even though I was in my 20s.)
1984 was sci-fi in the way it looked at the future of communications, notably the technical side, the constant surveillance, etc, but also cut across political fiction and various other genres as part of its speculations.