 I'm number 999 in the wait, you know, for the help desk. So I won't get out today. So I'm mad and I'm frustrated and I'm sad. Delta, American and United Airlines were hit the hardest by this outage. All three say that they resumed some flights this morning. It's still a big mess, though, as the cancellations and delays rippled across the system throughout the day. So, Jenna, that gets to the big question. How? How did this happen?