Jay Asher

When high school student Clay Jenkins receives a box in the mail containing thirteen cassette tapes recorded by his classmate Hannah, who committed suicide, he spends a bewildering and heartbreaking night crisscrossing their town, listening to Hannah's voice recounting the events leading up to her death.

It's 1996, and less than half of all American high school students have ever used the Internet.
Emma just got her first computer and an America Online CD-ROM.
Josh is her best friend. They power up and log on—and discover themselves on Facebook, fifteen years in the future.
Everybody wonders what their Destiny will be. Josh and Emma are about to find out.