Persians, unlike the Arabs, follow a solar calendar where the year begins on the day of vernal equinox (21st March). Akbar's calendar was based on the Persian model. Though introduced in 1584 AD, Akbar had the calendar backdated to start on 21st of March of 1556 AD which was the year he had ascended the throne. This was the year 963 in the Hijri era.

Bengal adopted Akbar's calendar with certain modifications. In 1556 AD, the Bengali calendar was assigned the year 963 to coincide with the year in Hijri era which today reads 1418. It is 1406 in the Bengali year.If we recall that a solar year is about 11 days longer than the lunar year, it is not difficult to figure out why the Hijri era has marched ahead by: [11 X (1998 - 1556)] days = 13 years in the 442 years since 1556 AD.

There is one other significant difference with Akbar's calendar which, like the Persian calendar and the Christian calendar, had months of fixed number of days. The Bengali month, on the other hand, is based on the ancient Sanskrit treatise, "Surya Siddhanta" where the months are assigned by the zodiac sign. The sun's stay under a zodiac sign varies from year to year. That is why any Bengali month can vary in length anywhere from 29 to 32 days. The sun enters the Mesh Rashi (Aries) on 15th of April, give or take a day.This marks the beginning of the Bengali year and is celebrated as the first of Baishakh.

The Bengali calendar is a prime example of the eclectic spirit that had prevailed during the rule of Emperor Akbar. It was a synthesis of features from ancient Indian calendars based on "Surya Siddhanta" with those of the Hijri calendar and the Persina calendar. No wonder that the Bengali calendar is catering successfully to the needs of a quarter billion Muslims and Hindus of Bangladesh and Eastern India.

Like Sanskrit, Apabhramsa-Avahattha was a literary language, and in the available records it shows remarkably little local variation; practically the same form of the language appears in the poems written in Gujrat and in Bengal. But the spoken language conditioned by the regional linguistic and ethnic environments took up the different regional New Indo-Aryan languages. The emergence of these New Indo-Aryan speeches was not all synchronized. But some of them, including Bengali, certainly originated by the middle of the tenth century at the latest.

For old Bengali the only records are mystic carya songs discovered in a MS from Nepal by Haraprasad Shastri.The language of the carya songs is basically vernacular, but at the same time it is also something of a literary language.

Bengali at the present day has two literary styles. One is called "Sadhubhasa" (elegant language) and the other "Chaltibhasa" (current language) . The former is the traditional literary style based on Middle Bengali of the sixteenth century. The later is practically a creation of the present century, and is based on the cultivated form of the dialect spoken in Calcutta by the educated people originally coming from districts bordering on the lower reaches of the Hoogly. The difference between the two literary styles is not very sharp. The vocabulary is practically the same. The difference lies mainly in the forms of the pronoun and the verb. The Sadhubhasa has the old and heavier forms while the Chalitbhasa uses the modern and lighter forms. The former shows a partiality for lexical words and for compound words of the Sanskrit type, and the latter prefers colloquial words, phrases and idioms. The Chalitbhasa was first seriously taken up by Pramatha Chaudhuri at the instance of Rabindranath Tagore during the early years of the first World War. Soon after Tagore practically discarded Sadhubhasa, and Chalitbhasa is now generally favored by writers who have no particular fascination for the traditional literary style. The Sadhubhasa is always easy to write but it is somewhat faded in signification and jaded in rhythm.

The Bengali script, like all other Indian scripts, originated from Brahmi alphabet of the Asokan inscriptions.The Bengali alphabet in its present printed form took shape in 1778 when printing types were first cast by Charles Wilkins. There still remained a few archaic forms and these were finally replaced in the middle of the nineteenth century.