I'm riiight on the cusp; born in '82, graduated in 2000. My wife was born in '81, graduated in '99. We're definitely more millenial than GenX - my older siblings (born in '70, '72, '75) are total GenX'ers. The GenX'ers had computers as tweens/teens, so they definitely grew up as all this tech stuff was developing, but I've literally never lived in a house without a computer. Quite literally: my parents bought a ZX-81 for my older siblings the same week I was born.
We both have younger siblings who were born in '84 (graduated in high school 2002). They're the oldest of what I'd call "true millenials" - I think one of the big distinguishing things is that those who graduated after 2000 had Facebook in college, whereas I didn't. Sure, there was ICQ, IRC, various web forums, Myspace and Friendster and all that stuff, but it wasn't quite the same; those didn't have nearly the reach of Facebook, and most of the people I interacted with pre-facebook I didn't know IRL. I used Facebook to keep in touch with College friends after we all graduated and did the whole post-college-diaspora thing, but my brother and his friends used Facebook constantly as a key part of their social life.
Additionally, cell phones were much more prevalent for the "true millenials" - my brother and I both got cell phones in '03, and for him it was a core part of his college experience.
Facebook as a determiner is an interesting one. I'm also on the cusp but delayed uni by a few years, and so Facebook popped up while I was at uni and changed everything.
That's pretty much exactly what I said; those graduating HS after 2000 didn't have FB in college. I graduated high school in 2000, college in '04, didn't have facebook till after graduation. My brother graduated HS in 2002, college in 2006, facebooked all the time.
We both have younger siblings who were born in '84 (graduated in high school 2002). They're the oldest of what I'd call "true millenials" - I think one of the big distinguishing things is that those who graduated after 2000 had Facebook in college, whereas I didn't. Sure, there was ICQ, IRC, various web forums, Myspace and Friendster and all that stuff, but it wasn't quite the same; those didn't have nearly the reach of Facebook, and most of the people I interacted with pre-facebook I didn't know IRL. I used Facebook to keep in touch with College friends after we all graduated and did the whole post-college-diaspora thing, but my brother and his friends used Facebook constantly as a key part of their social life.
Additionally, cell phones were much more prevalent for the "true millenials" - my brother and I both got cell phones in '03, and for him it was a core part of his college experience.