Basically back in the year 1999, people thought the world was going to end because the computers would crash if the year got set to 2000 because of a coding bug. And instead of re-coding it, people started running up and down the streets yelling "#Y2K"
So this question goes to the '90s kids, how did you react to all of this?
(I find all of this pretty interesting, and #2k12 was pretty funny too lol)