Question

what is a foreshadowing?

Answer 1

INDIRECTLY HINTING at plot points that occur later in the story

Answer 2

When foreshadowing is done well, you experience a feeling of "Oh, of course" even in a turn of events that will be, at the onset, surprising. You should feel simultaneously that you did not expect this particular twist in the plot, and that it fits in with the rest of the story perfectly. When the surprising turn of events comes right at the end, that feeling is enhanced.