If we had to pick one moment that made IU the superstar that she is today, many would point to this particular song.
IU's 2010 lead single 'Good Day' is a song that is responsible for her rise to superstardom.
While it is almost difficult to imagine there was a time IU wasn't incredibly famous, this 24-year-old star didn't see the light of day until two years after her debut.
'Good Day,' which became an instant hit, allowed IU to show off her impressive ability to hit the high notes, especially the three rising high notes towards the end of the song. She was able to sing the high notes with such ease and grace that for a long time "the three rising high notes" were what she was known for.
IU revisited that glorious moment when she performed 'Good Day' at the Sudden Attack Champions League 2017.
"It's been seven years since [Good Day's] release, but it is just as good as the first time I listened to it," commented one fan.
There is no question that this song made IU's big break possible!
By Gothesun and Arin Kim firstname.lastname@example.org