Guess Who?

Guess Who? (נחש מי?) is a two-player board game in which players each guess the identity of the other's chosen character. The game was developed by Israeli game inventors Ora and Theo Coster, the founders of Theora Design. It was first released in Dutch in 1979 under the name Wie is het? Milton Bradley then produced the game in the United Kingdom, and it was brought to the United States in 1982. It is now owned by Hasbro.

Gameplay
Each player starts the game with a board that includes cartoon images of 24 people and their first names with all the images standing up. Each player selects a card of their choice from a separate pile of cards containing the same 24 images. The objective of the game is to be the first to determine which card one's opponent has selected. Players alternate asking various yes or no questions to eliminate some of the candidates, such as:


 * "Does your person wear a hat?"
 * "Does your person wear glasses?"
 * "Is your person a man?"

The player will then eliminate candidates (based on the opponent's response) by flipping those images down until only one is left. Well-crafted questions allow players to eliminate one or more possible cards.

Editions
Special editions which have different faces have been released, including Star Wars (released 2008 with 24 characters, and 2014 with 15 characters), Batman (released 2019), Animal Crossing (2019), Marvel Comics (released 2022, 24 characters), Super Mario (2022), Disney, Mr. Men, Peppa Pig and The Simpsons. There are smaller, "travel" editions that have only 20 different faces. In 2008 and 2010, extra and mix and match games were released. A computer game based on the series was released in 1999 by Hasbro Interactive/Infogrames.

Advertising
In the United States, advertisements for the board game often showed the characters on the cards coming to life and making witty comments to each other. This caused later editions of such ads to carry the spoken disclaimer line "game cards do not actually talk" to meet Federal Trade Commission advertising guidelines requiring full disclosure of toy features unable to be replicated with the actual product.

Strategy
Popular belief is that a binary search is the most efficient approach to the game, with which each question halves the number of possible identities. This can be applied by asking complex questions - such as "Does your character have red hair, or glasses, or a big nose?" - where a yes or a no eliminates exactly half of the remaining characters. Such a strategy takes only four questions to reduce the field to three people, giving the fifth question a 50/50 chance of identifying the opponent's character.

The game was strongly solved by Mihai Nica in 2016. Nica's research found that while a player was ahead their optimal strategy was a binary search, and when behind they should instead make "bold plays" that had a chance of narrowing things down significantly, in order to pull ahead of the other player. Using this method, the first player has a 63% chance of winning under optimal play by both sides.

Use in education
Guess Who? has found use in an educational context,  including the development of deductive reasoning skills. In addition, the game can be used for a wide range of speech and language development goals, including:
 * Articulation
 * Comprehension
 * Question formation
 * Describing salient features
 * Vocabulary in foreign languages

Criticism of lack of diversity
Modern commentators have noted a bias toward white and male characters in Guess Who?. In 2012, a freelance journalist wrote to Hasbro on behalf of her six-year-old daughter, asking why there were only five female characters to choose from, against nineteen male. Hasbro's response noted that each characteristic in the game – such as wearing glasses, or having red hair – was based on a numerical equation, and deliberately appeared exactly five times. The company wrote that the game was intended to "draw attention away from using gender or ethnicity as the focal point, and to concentrate on those things that we all have in common, rather than focus on our differences".

In response to Hasbro's statement, the mother said that she thought identifying physical differences was "the whole point" of the game, and asked "Why is female gender regarded as a 'characteristic', while male gender is not?" The New Statesman criticized the "tone-deafness" of Hasbro's remarks.

Some editions of the game since the early 2000s have included more women.

The original version of Guess Who? featured only one non-white character – Anne, a black woman who was redrawn in a subsequent edition as white. More recently, Hasbro has redesigned the board to feature a more racially diverse set of people.

Television adaptation
On April 19, 2021, Deadline Hollywood announced that a planned unscripted television adaptation of the board game was in early development at NBC and will be produced by Endemol Shine North America and Entertainment One (Hasbro's subsidiary).