Half of my parents' house just went dark

[will_fox]

idk what's happening at my parents' place. we were just hanging out, doing nothing unusual, and suddenly half the house went dark!
multiple outlets, the whole living room, and the dining room are totally dead. I checked the main panel, and none of the breakers looked tripped!
I even tried flipping them all off and back on, but nothing changed. what is going on here, any quick ideas on what could kill half a house like this without visibly tripping a breaker?

 

[h0td0g]

there probably was a lost phase from the utility company. Do you have any 240v appliances and are they working? that's a telltale sign that you've lost a phase

 

[electr0roy]

you need to check the big stuff! go try the electric stove, dryer, or A/C. if those aren't working, or only work halfway, you definitely lost a leg of power from the utility company
it happens sometimes with fallen branches or transformer issues
give the electric company a call and they usually fix that for free