"Lollipop" is a song by Big Bang and 2NE1, created to promote a cellphone by LG Cyon. It interpolates the 1958 hit "Lollipop" written by Julius Dixson and Beverly Ross. The song hit the top spot on various online charts, including a 4-week #1 run on music portal M.Net. "Lollipop" was used to debut 2NE1 unofficially, as it does not serve as their debut single. DJ Wreckx remixed the song for Cyon Bboy Championships. The song went to sell over 3 million digital downloads and became a huge-hit in South Korea, topping the Cyworld chart for April 2009.

2NE1 followed up with their "debut" single "Fire".

The song was used for cellphone LG Cyon. It charted number one on offline charts and online charts in Korea. It was not performed on any TV show except YG's 2010 Tour. "Fire" was marked as 2NE1's official debut.

The video was filmed in the first week of March 2009. It premiered on March 28, 2009. The video shows both groups dancing together in rainbow and multi-colored shot. A behind the scenes version was premiered a few weeks later on May 2, 2009. The video was directed by Hyun Young-seong.

The original synopsis shows 2NE1 singing in front of a white screen for the intro, Then, it shows Big Bang And 2NE1 in a colour room (The colours are normally Red, Yellow, Blue), It also shown:

A re-edit version was made, it did not show the bit of 2NE1 in front of the white screen, it was replaced with Dara in her blue room (who really sung the verse), there are a few scenes changed and new scenes with the LG CYON phones.

http://www.metrolyrics.com/lollipop-lyrics-big-bang.html

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Wikipedia