Nayutawave Records released a Japanese-language version of "Gee" on October 20, 2010, as the group's second single in Japan.

"Gee" is primarily a bubblegum track with an electropop and Europop sound brought by prominent techno- and hip hop-influenced synthesizers and beats.

The song was supported by a music video depicting the group members as mannequins who, after the shop owner leaves, come to life and perform the choreography in colored skinny jeans.

In November, SM released the group's debut studio album, which was supported by singles including "Into the New World" and "Girls' Generation"; the latter of which was among the top three most popular songs of 2007 according to a Gallup Korea public poll.

[4][5] On January 5, 2009, SM released Gee, the group's first extended play (EP) (known in South Korea as "mini album").

[6] SM had planned to release "Dancing Queen", a cover version of Duffy's single "Mercy (2008), as the title track.

[7] The plan was inspired by the "retro" music trend caused by fellow idol group Wonder Girls' hit single "Nobody" (2008).

[9] Production duo E-Tribe, who wrote "Gee", pitched the song to SM, who thought the lyrics were childish and the melody weak.

[11] "Gee" was written, arranged, and produced by E-Tribe, a production duo consisting of Ahn Myung-won and Kim Young-deuk.

[14] The group members sing in high-registered vocals accentuated with electronic processing including bleeps and clicks.

According to musicologist Michael Fuhr, this vocal technique demonstrates aegyo, a Korean concept for cuteness in an adolescent, feminine way.

The performance was preceded by a video interlude entitled The Secret of "Gee" including Jessica and Tiffany respectively dancing Heechul's and Kangin's parts in "Sorry, Sorry" during a Girls' Generation dance practice before the practice is infiltrated as a prank by Heechul, Kangin, Leeteuk and Sungmin respectively disguised as Jessica, Tiffany, Taeyeon and Sunny.

He further recognized the "formally irrefutable" song as overcoming half a millennium of historical animosity to broker pop cultural peace between South Korea and Japan for only one year.

[14] Billboard magazine labelled "Gee" "arguably the most iconic K-pop song in the past ten years.

"[65] In 2023, Rolling Stone named "Gee" the greatest song in the history of Korean pop music, referring to it as "a pure distillation of the giddiness of infatuation".