On Dec. 20, 2013, Justine Sacco boarded a series of flights that would take her from her home in New York City to South Africa, where she planned to spend her holiday. During the trip, she haphazardly typed out a series of tweets to her mere 170 followers. She tweeted about the body odor of a German man sitting near her. She tweeted about the bad teeth found in the mouths of fellow travelers in London.

And just before she took off for her flight to Cape Town, she typed out one final tweet—“Going to Africa. Hope I don’t get AIDS. Just kidding, I’m white.”