Happy Together is one of the most popular shows on Korean free-to-air networks which airs every Thursday at 23:05 (KST).
The early Happy Together was a talk show, and a quiz where the MC's face students for scholarships.
Later that was scrapped and the Classroom Talk (책가방토크) and the Metal Tray Karaoke Room were implemented as permanent corners.
A highlight episode was shown on April 28, 2005, as the finale to Season 1, where ratings were slightly lower than usual.
3 chance cards are available to ease the singing, and as soon as someone makes a mistake, the metal trays suspended above their heads will drop on them.
Usually involving funny antics, anyone who laughs or forgets what to do (known as NG) will be hit by a metal tray.
They are each assigned a note (Do, Re, Mi, Fa, So, La, Ti, Do) and would have four chances to correctly play the song by hitting the corresponding key on the keyboard with their heads.
Season 2 was commonly known as Happy Together Friends (해피투게더 프렌즈), where celebrities find their former schoolmates.
The program originally began as a pilot which aired in February 2005 titled Friends, hosted by Yoo Jae-suk, Eugene, and Tak Jae-hoon.
A picture of the object/person is put on to a conveyor belt and it passes through each participant while they are wearing headphones, they must correctly identify what it is or be hit by the Metal Trays (or be forced to raise their hands in the pilot).
Those who escape the sauna can enjoy food and drinks while watching the rest of the challengers suffer.
These conversations usually surround what a typical "Korean mother" (아줌마) will talk about, those who laugh will be sprayed by a water gun.
This programme has received the highest ratings of Thursday night prime-time lineups since its beginning.
Due to its popularity, programs on SBS and MBC at the 11:05 pm timeslot have suffered from Happy Together over the years.
Mystery Hunters (미스터리 특공대) and Love Generation (연애시대) began airing in 2008 and both were cancelled after 3 months due to low ratings.
Entertainment Tonight (한밤의 TV연예) moved to that timeslot on SBS but is suffering from low ratings as well.