The tiles must form words that, in crossword fashion, read left to right in rows or downward in columns and are included in a standard dictionary or lexicon.

Scrabble is produced in the United States and Canada by Hasbro, under the brands of both of its subsidiaries, Milton Bradley and Parker Brothers.

In 2008, Hasbro changed the colors of the premium squares to orange for TW, red for DW, blue for DL, and green for TL, but the original premium square color scheme is still preferred for Scrabble boards used in tournaments.

[7]: 100  In 1949, Brunot and his family made sets in a converted former schoolhouse in Dodgingtown, Connecticut, a section of Newtown.

The Scrabble game show ran from July 1984 to March 1990,[13] with a second run from January to June 1993.

This rule differs slightly in most tournaments; a player who plays out adds twice this sum, and the opponent's score is unchanged.

The score for a play is determined as follows: Scoreless turns can occur when a player passes, exchanges tiles, loses a challenge, or otherwise makes an illegal move.

Words that contain apostrophes, are hyphenated or capitalized (such as proper nouns) are generally not allowed unless they also appear as acceptable entries; for example, words such as HERES, JACK and TEXAS, while typically containing an apostrophe or considered a proper noun, have unrelated meanings and are therefore acceptable in major Scrabble lexicons.

Acronyms and abbreviations are generally not allowed unless they have separate entries (such as AWOL, RADAR, SCUBA, and WYSIWYG[19]).

Vulgar and offensive words are generally excluded from the Official Scrabble Players Dictionary but allowed in club and tournament play.

The North American Scrabble Players Association removed slurs from its lexicon in 2020, after conducting a poll of its members.

There is also a large community of competitive Collins players in North America, with its own NASPA rating system.

The NWL and OSPD are compiled using a number of major college-level dictionaries, principally those published by Merriam-Webster.

The key difference between the OSPD and the NWL is that the OSPD is marketed for "home and school" use, without words which their source dictionaries judged offensive, rendering the Official Scrabble Players Dictionary less fit for official Scrabble play.

NASPA, the Word Game Players Organization, and Collins Coalition (CoCo) all sanction CSW tournaments, using separate Elo rating systems.

[50] When only adding the word SESQUIOXIDIZING to these official lists, one could theoretically score 2015 (OSPD) and 2044 (SOWPODS) points in a single move.

[51] The highest reported combined score for a theoretical game based on SOWPODS is 4046 points, constructed by Nathan Hedt of Australia.

In August 1984, Peter Finan and Neil Smith played Scrabble for 153 hours at St. Anselm's College, Birkenhead, Merseyside, setting a new duration record.

The official Scrabble computer game in North America uses a version of Maven as its artificial intelligence and is published by Atari.

Quackle is an open-source alternative to Maven of comparable strength, created by a five-person team led by Jason Katz-Brown.

The Nintendo DS version of Scrabble 2007 Edition made news when parents became angry over the game's AI using potentially offensive language during gameplay.

Facebook initially offered a variation of Scrabble called Scrabulous as a third-party application add-on.

[67] Four days later, Scrabulous was disabled for users in North America,[68] eventually reappearing as "Lexulous" in September 2008, with changes made to distinguish it from Scrabble.

Electronic Arts have also released mobile apps for Android and iOS, allowing players to continue the same game on more than one platform.

For example, Literati draws random tiles instead of providing a finite number of tiles for the game, assigns different point levels to each letter and has a slightly different board layout, whereas Lexulous assigns eight letters to each player instead of seven.

Word games similar to or influenced by Scrabble include Bananagrams, Boggle, Dabble, Nab-It!, Perquackey, Puzzlage, Quiddler, Scribbage, Tapple, Upwords, and WordSpot.

Editions are available for travelers who may wish to play in a conveyance such as a train or plane or to pause a game in progress and resume later.

These include editions on a rotating turntable, so players can always face the board, with the letters upright and a raised grid that holds the tiles in place.

[83][84] Also available are alternative Scrabble boards, often made of glass[85] or hardwood, that have superior rotating mechanisms and personalized graphics.

An edition has been released (in association with the Royal National Institute of Blind People (RNIB))[86] with a larger board and letters for players with impaired vision.