“Fireflies”, Owl City’s debut single, was an international smash hit, effectively launching the genre Twee into the mainstream. It reached #1 in the US in November 2009.

The song was inspired by watching shooting stars during a camping trip with lyrics also influenced by insomnia. Adam Young said of “Fireflies” in an interview with Female First:

I have a bit of a problem falling asleep. Strangely enough it is when I can’t sleep that I tend to find most inspiration. I was up late and in the basement one night when I wrote ‘Fireflies’. I was sitting at the keyboard just fooling around, not really trying to write anything. Over the next couple of hours that song came together in the most natural way. I can’t explain it but it almost wrote itself. I didn’t have any idea that moment that I had written a hit.

The song also features uncredited vocals from the lead vocalist from Relient K, Matthew Thiessen.