Survivor (U.S.)

Survivor is a U.S. reality-based competition television show.

The United States version is produced by CBS, and is currently aired at 8 pm during Wednesdays (formerly Thursdays).

History
Starting with season 39, Canadians are eligible to apply for the show.

Format Variations
While the United States version introduced the standard Survivor format in, subsequent seasons introduced several game-changing twists to keep the contest exciting and fresh.

Number of Members per Tribe
For the first seven seasons, there were two tribes of eight members (picked by production, picked by the oldest contestants, and gender). For seasons with 18 contestants and two tribes, contestants could either be divided by gender or heterogeneously, with one tribe having 4 women and 5 men and the other tribe having the opposite.

"Versus"/Themed Seasons
As per consensus of the producers, a batch of contestants could be sorted into tribes with a common theme, sometimes based on the cast's personal attributes. Some seasons have contestants be joined with returning players, all of which have certain similar attributes.
 * Gender: First seen in, followed by and , the tribes were divided based on their gender, pitting the men against the women. Typically the tribes are switched up later in the game.
 * All returning players: In, , , and , 18 to 20 past players returning to play the game.
 * One returnee per tribe: In, , , and , one returning contestant joined one tribe, making them full-fledged players of the game. In Guatemala, Stephenie LaGrossa and Bobby Jon Drinkard, who were the last remaining members of the ill-fated Ulong tribe were given a second chance. In Redemption Island, Rob Mariano and Russell Hantz settled their rivalry dating back from . In South Pacific, Coach Wade and Ozzy Lusth joined the game under the premise that they were popular to have terrible social games in their previous outings. In Philippines, Jonathan Penner, Russell Swan, and Michael Skupin were all medically evacuated in their previous seasons. expanded on this format, bringing back four former castaways and assigning two to each tribe of new players.
 * Age and Gender: In, its 16 contestants were divided into four tribes of four according to age and gender: Younger men, younger women, older women, and older men.
 * Ethnicity: In a rather controversial move, the castaways of were divided into four tribes of five according to their ethnicity: Hispanic, Caucasian, African, and Asian.
 * Haves vs. Have Nots: had the Haves vs. Have Nots twist. Known as one of the worst twists in Survivor history, the "Haves" tribe was given all of the luxuries needed for living, and the "Have Nots" tribe was given little to nothing.
 * Heroes vs. Villains: featured two tribes defined by popularity or infamy. The Heroes were picked for being deemed to play the game with integrity, courage and honor, while the Villains were picked due to their skills in manipulation, deception and overall notoriety.
 * Age: In, the tribes were defined according to age, with an entire tribe of younger players and an entire tribe of older players. This theme returned in the form of.
 * : and  featured pairs of contestants with a pre-existing relationship. In the first Blood vs. Water, a tribe of former contestants were pitted against their loved ones who were playing for the first time. In the second version, an all-new batch of contestants underwent the same twist.
 * Fans vs. Favorites: and  had 10 self-proclaimed "superfans" of the show that were pitted against 10 fan favorites from seasons past.
 * Brawn vs. Brains vs. Beauty: In and, the tribes were divided into 3 tribes of 6 according to the contestants' best attribute that gets them by in life: Intellect, physical strength, or physical appearance and/or social skills.
 * White Collar vs. Blue Collar vs. No Collar: In, the tribes were divided into 3 tribes of 6 according to the contestants' social class of occupation.
 * Game Changers: In, Survivor brought back 20 former players who were proclaimed as game changers, people who tried to change the game.
 * Heroes vs. Healers vs. Hustlers: Contestants are separated based on praised qualities about themselves.
 * David vs. Goliath: The castaways were divided into two tribes based on their degree of success in life: the underdogs (David) and the overachievers (Goliath).

Tribe Switch and Dissolves
Main Article: Tribe Switch and Tribe Dissolve A tribe dissolve is when there are more than two tribes in the season and the remaining contestants are placed in only two tribes. Either the contestants in the other tribe(s) are placed in the two tribes (seen in and ) or all castaways are shuffled in the two tribes (seen in, , and ). A tribe switch is simply a game twist that shuffles the tribe affiliations.

One World
Main article: One World (twist) 

Losers Bracket Formats
Named as such by Jeff Probst, the Losers Bracket provides an opportunity for an eliminated contestant (excluding quitters and medevaced players) to re-enter the game.

Seasons
Survivor has filmed 38 seasons as of January 2018, and has aired 37.

Viewership Note: Starting in the 2013-2014 series rankings ( and ), the two seasons aired in that time are listed under Survivor, rather than separately.