Braille

Braille is a communications-based Decryption element, meant as a writing system for the blind or visually-impaired. Braille is one of the most commonly-used ciphers in puzzlehunting, along with Morse Code, Flag Semaphore, and five-bit Binary.

Background
See also: Braille

Puzzle Applications
Braille is an international system, with a correspondence in place for many world languages. While some puzzles may make use of a different system, most puzzles will limit themselves to the 26 patterns that correspond to letters in the English alphabet.

Braille's main draw in puzzling comes in its role as an extraction element. Many puzzles employ Braille by providing a grid and mapping onto it some form of binary input:

This form of extraction can come clued or unclued, though clued is significantly more common. Other puzzles will ask the solver to make the grid themselves using an ordering mechanism and appropriate chunking.

Braille dots also have a canonical numbering scheme; the dots are numbered such that the first column contains dots 1-3 and the right column contains dots 4-6, both labeled top-to-bottom (so N ⠝ would use dots 1, 3, 4, and 5). This is the schema used in the names of the Braille characters in Unicode, and sees occasional use in puzzles.

Braille gets plenty of press as a standard code, too—puzzles may have Braille dots on the page that require translation, or a phrase that requires translation into Braille to use the properties of the Braille characters themselves, such as the number of dots.

Spotting the usage of Braille
Where it isn't immediately apparent (i.e. dot patterns present immediately on the page), the usage of Braille is often clued using the title or flavortext—references to being visually impaired in some way ("dark", "blind") or the tactile nature of Braille ("feel", "touch") are particularly good indicators of the usage of Braille.

Regardless of whether flavortext hints at it or not, be on the lookout for grids, especially 2x3 grids or grids divisible into 2x3 grids, whose cells can be assigned one of two values. This is the clearest indicator of Braille being an important element to the puzzle, though sometimes it will turn out to be a Bitmap instead.

Translating Braille
insert an image of the decade table.

Many Braille charts and interpreters can be found online. To save time on transcription, however, one may wish to memorize the twenty-six letters of the English alphabet in Braille, which is enough to cover most uses of Braille in puzzlehunts.

Braille letters are organized into decades. The ten symbols representing A-J compose the first decade and contain no bottom-row dots; these must be memorized. Most of the remaining letters are just the first decade with additional dots on the lower row: letters K-T (the second decade) are just A-J with an additional dot 3 (⠄), while U-Z (the first half of the third decade, ignoring W) are just A-E with additional dots 3 and 6 (⠤). W (⠺) is a special case that needs to be memorized (as W, not in the French alphabet at the time, was skipped and added later to accommodate English): it is a J with an extra dot 6.