Clusters of consonants are represented by different and sometimes quite irregular characters; thus, learning to read the script is complicated by the sheer size of the full set of characters and character combinations, numbering about 500. While efforts at standardizing the script for the Bengali language continue in such notable centers as the Bangla Academies (unaffiliated) at Dhaka (Bangladesh) and Kolkata (West Bengal, India), it is still not quite uniform as yet, as many people continue to use various archaic forms of letters, resulting in concurrent forms for the same sounds. Among the various regional variations within this script, only the Assamese and Bengali variations exist today in the formalized system.
It seems likely that the standardization of the script will be greatly influenced by the need to typeset it on computers. The large alphabet can be represented, with a great deal of ingenuity, within the ASCII character set, omitting certain irregular conjuncts. Work has been underway since around 2001 to develop Unicode fonts, and it seems likely that it will split into two variants, traditional and modern." - Wikipedia article on Bengali Script
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