# Scrabble/Rules
## Equipment

Standard playing equipment includes:
* 15x15 Scrabble board
* Standard set of 100 tiles according to the usual distribution, placed in an opaque bag or face-down on the table (a bag is required in tournament play)
* One rack per player
* Paper and pencil

## Goal

The goal of Scrabble is to score as many points as possible by placing letter tiles to create words onto the game board. At the end of the game, when one player has used all of their tiles and there are no more tiles left to draw, the game ends.

## Before the game

Players should agree on a dictionary or word source to be used, for the purpose of adjudicating challenges.
The game is set up so that each player possesses one rack. The 100 letter tiles are placed into an opaque bag (or face-down), hidden from view. Each player draws one tile to determine order of play. The player with the letter closest to "A" in the alphabet, with the blanks taking precedence over "A," goes first, and play proceeds clockwise. If two players tie for first, repeat.
Players return tiles to the bag, and shuffle. Each player draws seven tiles, and places them on their rack, hidden from other players.

### Tournament play

Since having all 100 tiles is crucial to tournament game play, players should confirm that the Scrabble set contains 100 tiles (this is usually done by arranging the tiles into four 5x5 squares, or one 10x10 square). In most tournament games, the player with the fewer number of firsts will go first; if there is a tie, the player with the most number of seconds goes first. If there is still a tie, both players draw one tile, as described above.

## Gameplay

The first word formed must consist of at least two letters that form a word reading left-to-right or top-to-bottom, and touch the center square (H8, marked with a star). On every turn, the player has the option to:
* Pass their turn, scoring nothing.
* Exchange 1-7 tiles, scoring nothing. The proper way to exchange tiles is to place the exchanged tiles face down, draw replacement tiles, and put the exchanged tiles into the bag. You can only exchange if there are at least 7 tiles in the bag.
* Make a play by adding at least one new tile to the board, record the score for the play, and add to their cumulative score.
After making a play, the player announces the score for that play, and draws replacement tiles until they have seven tiles. Every play thereafter must connect to at least one tile already on the board. On subsequent plays, players can
* Extend a previously played word; e.g. if PARK is played, (PARK)S, (PARK)ING, RE(PARK) and RE(PARK)ING are all acceptable plays.
* "Hook" a word by adding one letter to a previously played word, and playing perpendicular (e.g. if PARK is played, playing ZEALOTS/S(PARK) is valid).
* Playing parallel to a previously-played word. For example, playing ILEA under PARK, forming PI, AL, RE, and KA.
Some rules about subsequent plays:
* Diagonal plays or words that read right-to-left or bottom-to-top (e.g. SEIVARG*) are not acceptable.
* All letters played in one turn must lie on a line and form a continuous word (usually called the "main word"). At least one tile played must be adjacent to a tile previously on the board.
Plays that violate the above conditions are unacceptable, and can be challenged off in tournament play, regardless of validity.
There are two blank tiles, which may be used as any letter. Blank tiles score 0 points, regardless of the letter it designates. When a blank is played, the letter that the blank represents must be indicated, and cannot change in subsequent turns. It can however be swapped.

### Acceptable words

All words in the agreed-upon dictionary, including inflections, are acceptable. Proper nouns are not acceptable, unless they have separate meanings (such as CHINA, JACK, or BOSTON). Most acronyms or abbreviations are not allowed, unless they appear as separate entries. Archaic spellings are generally not allowed. Foreign words which have been incorporated into the language are valid. Vulgar and offensive words are acceptable in tournament and most club play (however, the National School Scrabble Championship uses the OSPD5, which expurgates offensive words).
The official word list in North American tournament play is the Official Club and Tournament Word List, 3nd Edition. In other countries, the official word list is Collins Scrabble Words (CSW), 2015 edition.
Note: Words that are only acceptable in CSW, but not TWL, are commonly denoted by a #.

### Challenging a play

Main article: Challenging a play
If player A forms a word that the opponent believes is invalid (not listed in the agreed-upon dictionary), the opponent can challenge the play.. If any of the challenged word(s) does not appear in the dictionary, player A removes their play from the board and loses their turn. The opponent can only challenge a play before player A draws replenishment tiles. See article on "Challenging a play" for more details.

### End of the game

Under North American tournament rules, the game ends when:
* There are no more tiles left to draw, and one player has used up their tiles (known as playing out), or
* Six consecutive scoreless turns have occurred.
If a player plays out, the sum of the values of their opponents' tiles is added to the player's score, while each of the opponents' scores is reduced by the sum left on their own rack. In tournament play, the player playing out receives twice the value of their opponent's rack, and the opponent's score is unchanged. This does not affect point spread, but makes scoring slightly easier.

## Scoring

Each letter tile has a number next to it that indicates how many points it is worth. Common letters, such as vowels, are worth 1 point, while rare letters such as "Q", "X", and "Z" are worth 8-10 points. Blank tiles are worth zero points. The score of a play is equal to the sum of the scores of all new words formed (including extensions or hook words, see examples below).
Blank tiles can be swapped at the start of the turn for the corresponding letter. E.g., blank indicating R for the letter R.
* Double Letter Score and Triple Letter Score (DLS, TLS) - a letter on this space is doubled or tripled in its point value.
* Double Word Score and Triple Word Score (DWS, TWS) - if any letter touches this space, the entire word is doubled in point value. If your word includes both a letter bonus and a word bonus, the letter bonus is applied first, in accordance with order of operations.
Note that the center square is a DWS, so the first play of the game receives a double word score.
The premium letter squares are only applied on the first turn that they are used. On subsequent plays, the premium letter squares are nulled.
A play that covers two DWS is doubled then re-doubled (i.e. the score for the word is 4 times its face value) and is sometimes referred to as a "double-double." Similarly, a play covering two TWS is tripled then re-tripled ("triple-triple.").
If a player uses all seven of their tiles on one play, they receive an extra 50 points, in addition to the score for the word. Such a play is commonly referred to as a bingo or a bonus.
At the end of the game when nobody can make a move or someone goes out of tiles, each player subtracts the amount of points that remain unused on their rack from their total score. If someone goes out of tiles, then the total of points on all other players' racks is added to their score as well. For this reason it's usually advantageous to be the first to dump all your tiles.

### Example

Suppose player 1 plays FINED 8D. The score for this play is 2*(2*4 + 1 + 1 + 1 + 2) = 26 points. Suppose player 2 extends FINED to form CON(FINED) 8A. The score for this play is 3*(3+1+1+4+1+1+1+2) = 42 points. Note that the F on the DLS retains its face value. Suppose player 1 plays BATTInG 7G (with a blank N), forming BE and AD. The score for the main word, BATTInG is 2*3 + 1 + 2*1 + 1 + 1 + 0 + 2*2 = 15. The score for B(E) is 2*3 + 1 = 7 (note that the B is doubled both directions). The score for A(D) is 1+2 = 3. However, BATTInG uses all seven tiles, so it receives a 50 point bonus. The score for the play is 15+7+3+50 = 75. Player 1 has a 101-42 lead.

## Notation

Like chess, Scrabble uses a notation system to annotate plays. Rows are labelled 1-15, and columns A-O, as shown below. Each square has a unique coordinate, so the top left square would be A1 and the center star is H8.
| | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O |
| 1 | 3× WS | | | 2× LS | | | | 3× WS | | | | 2× LS | | | 3× WS |
| 2 | | 2× WS | | | | 3× LS | | | | 3× LS | | | | 2× WS | |
| 3 | | | 2× WS | | | | 2× LS | | 2× LS | | | | 2× WS | | |
| 4 | 2× LS | | | 2× WS | | | | 2× LS | | | | 2× WS | | | 2× LS |
| 5 | | | | | P3 | | | | | | 2× WS | | | | |
| 6 | | 3× LS | | | R1 | 3× LS | | | | 3× LS | | | | 3× LS | |
| 7 | | | 2× LS | | E1 | | 2× LS | | 2× LS | | | | 2× LS | | |
| 8 | 3× WS | | | 2× LS | Q10 | U1 | A1 | Y4 | | | | 2× LS | | | 3× WS |
| 9 | | | 2× LS | | U1 | | 2× LS | | 2× LS | | | | 2× LS | | |
| 10 | | 3× LS | | | E | 3× LS | | | | 3× LS | | | | 3× LS | |
| 11 | | | | | L1 | | | | | | 2× WS | | | | |
| 12 | 2× LS | | | 2× WS | S1 | | | 2× LS | | | | 2× WS | | | 2× LS |
| 13 | | | 2× WS | | | | 2× LS | | 2× LS | | | | 2× WS | | |
| 14 | | 2× WS | | | | 3× LS | | | | 3× LS | | | | 2× WS | |
| 15 | 3× WS | | | 2× LS | | | | 3× WS | | | | 2× LS | | | 3× WS |
Plays are usually notated in the form "WORD xy +score" where WORD indicates the main word played, xy is the coordinate of the first letter of the main word, and score is the score for the play. If the main word reads left-to-right, the row number precedes the column letter, and if the main word reads top-to-bottom, the column letter precedes the row number. All letters (except for blank tiles) are capitalized. Finally, if a word is played through one or more letters, the letters that were already on the board are surrounded by parentheses. For example, the first two plays of the game shown above are:
* QUAY 8E +32
* PRE(Q)UeLS E5 +122