The Bengali script was originally not associated with any particular language but was often used in the eastern regions of the Middle kingdoms of India and then in the Pala Empire. It later continued to be specifically used in the Bengal region. Today, the script holds official script status in Bangladesh and India, and it is associated with the daily life of Bengalis.
From a classificatory point of view, the Bengali script is an abugida: its vowel graphemes are mainly realized not as independent letters, but as diacritics modifying the vowel inherent in the base letter they are added to.
Bengali script is written from left to right and has no distinct letter cases. It is recognizable, as are other Brahmic scripts, by a distinctive horizontal line known as মাত্রা (matra) running along the tops of the letters that links them together.
The Bengali script can be divided into vowels and vowel diacritics/marks, consonants and consonant conjuncts (representing consonant clusters), diacritical and other symbols, digits, and punctuation marks. Vowels and consonants are used as alphabet and also as diacritical marks.
Romanization of Bengali is the representation of written Bengali language in the Latin script. The first people to employ the Latin alphabet in writing Bengali books were Portuguese missionaries stationed in Bengal in the 16th century. However, the Portuguese-based romanization did not take root.
In the late 18th century, romanization schemes based on the French and the English alphabet were developed and utilized.
Nowadays, various romanization systems for Bengali are used, most of which do not perfectly represent Bengali pronunciation.
Two standards are commonly used for transliteration of Indic languages, including Bengali. Many standards (like NLK/ISO), use diacritic marks and permit case markings for proper nouns. Schemes such as the Harvard-Kyoto one are more suited for ASCII-derivative keyboards and use upper- and lower-case letters contrastively, so forgo normal standards for English capitalization.