Literary braille is a code that differs from language to language, but the codes used for languages that share the English alphabet are related and have many features in common. All characters and indicators are defined as one or more six-dot cell patterns on a grid of two columns and three rows. All lower case letters and most common punctuation marks are the same.
Braille are strongly language-dependent.
Contracted braille is the standard, and even signs and literature intended for foreign readers is almost always available only in Grade 2 Braille. Several special codes very different from literary braille have been adopted for math, for computer codes, and for music, and these may differ strongly from country to country. The math and computer codes for the US and UK are totally different for example. An effort by the International Committee on English Braille is underway to develop an international Unified Braille Code for English-speaking countries. It cannot replace the present computer codes and is too clumsy for advanced scientific literature.