Bengali (Bangla)is an eastern Indo-Aryan language with around 300 million speakers mainly in Bangladesh, and in the Indian states of West Bengal, Tripura and South Assam. Bengali is the national and official language of Bangladesh, and one of the official languages in India. It is also spoken in the Andaman and Nicobar Islands. English, having no official status, is prevalent across government, law, business, media and education, and can be regarded as the de facto co-official language of Bangladesh. The indigenous people of northern and southeastern Bangladesh speak a variety of native languages.

The Bengali alphabet (বাংলা লিপি - Bangla lipi) is derived from the Brahmi alphabet. It is also closely related to the Devanagari alphabet, from which it started to diverge in the 11th Century AD. The current printed form of Bengali alphabet first appeared in 1778 when Charles Wilkins developed printing in Bengali. A few archaic letters were modernised during the 19th century.

Bengali has two literary styles: one is called Sadhubhasha (সাধুভাষা - "elegant language") and the other Chôlitôbhasha (চলিতভাষা "current language"). The former is the traditional literary style based on Middle Bengali of the sixteenth century, while the later is a 20th century creation and is based on the speech of educated people in Calcutta. The differences between the two styles are not huge and involve mainly forms of pronouns and verb conjugations.

Sources: http://omniglot.com/writing/bengali.htm
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