What is science fiction?

Yesterday, somebody asked me this.  At first I thought, what sort of question is that?  But it's actually a really good one.  Uhhh, it's about the future, no, the time doesn't really matter.  Sometimes they travel through it.  Technological advancements that have yet to occur in our present day.  Fighting robots?  That was my terrible answer, to a really good question.  It made me realize that a defrosted caveman would not stand a chance with me as an adviser.  Everything in Sci-Fi is a maybe.  Do I expect to laugh, for somebody to fall in love, to experience the truth of reality, for someone to get shot, for the good guys to win, or for time to be nonlinear?  Yep.  I expect all of it, and none of it to be shoved down my throat.  So the best answer to the initial question is.  It's fiction with a bigger imagination.