Crossword - Types of Grid

Types of Grid

• American-style grid

• British/South African-style grid

• Japanese-style grid

• Swedish-style grid

Crossword grids such as those appearing in most North American newspapers and magazines feature solid areas of white squares. Every letter is checked, and usually each answer is required to contain at least three letters. In such puzzles shaded squares are traditionally limited to about one-sixth of the design. Crossword grids elsewhere, such as in Britain, South Africa and Australia, have a lattice-like structure, with a higher percentage of shaded squares, leaving up to half the letters in an answer unchecked. For example, if the top row has an answer running all the way across, there will be no across answers in the second row.

Another tradition in puzzle design (in North America and Britain particularly) is that the grid should have 180-degree rotational symmetry, so that its pattern appears the same if the paper is turned upside down. Most puzzle designs also require that all white cells be orthogonally contiguous (that is, connected in one mass through shared sides, to form a single polyomino).

The design of Japanese crossword grids often follows two additional rules: that shaded cells may not share a side and that the corner squares must be white.

The "Swedish-Style" grid (picture crosswords) uses no clue numbers, as the clues are contained in the cells which would normally be shaded in other countries. Arrows indicate in which direction the clues have to be answered, vertical or horizontal. This style of grid is used in several countries other than Sweden, usually in magazines with pages of A4 or similar size, but also in the daily newspapers, covering entire pages. The grid often has one or more photos replacing a block of squares, as a clue to one or several answers, for example the name of a pop star, or some kind of rhyme or phrase that can be associated with the photo. These puzzles usually have no symmetry in the grid and instead often rely on a common theme (literature, music, nature, geography, events a special year etc.) as the foundation of the combination of illustrated clues and other blocks of clues.

Substantial variants from the usual forms exist. Two of the common ones are barred crosswords, which use bold lines between squares (instead of shaded squares) to separate answers, and circular designs, with answers entered either radially or in concentric circles. Free form crosswords (criss-cross puzzles) have simple, asymmetric designs, and are often seen on school worksheets, kids' menus, and other entertainment for children. Grids forming shapes other than squares are also occasionally used.

Puzzles are often one of several standard sizes. For example, many weekday puzzles (such as the New York Times crossword) are 15×15 squares, while weekend puzzles may be 21×21, 23×23, or 25×25. The New York Times puzzles also set a common pattern for American crosswords by increasing in difficulty throughout the week: the Monday puzzles are the easiest and the puzzles get harder until Saturday. The larger Sunday puzzle is approximately the same level of difficulty as a weekday-size Thursday puzzle. This has led U.S. solvers to use the day of the week as a shorthand when describing how hard a puzzle is: i.e., an easy puzzle may be referred to as a Monday or Tuesday, a medium-difficulty puzzle as a Wednesday and a truly difficult puzzle as a Saturday.

Typically clues appear outside the grid, divided into an Across list and a Down list; the first cell of each entry contains a number referenced by the clue lists. For example, the answer to a clue labeled "17-Down" is entered with the first letter in the cell numbered "17", proceeding down from there. Numbers are almost never repeated; numbered cells are labeled consecutively, usually from left to right across each row, starting with the top row and proceeding downward. Some Japanese crosswords are numbered from top to bottom down each column, starting with the leftmost column and proceeding right.