Devanagari is a Unicode block containing characters for writing languages such as Hindi, Marathi, Bodo, Maithili, Sindhi, Nepali, and Sanskrit, among others. In its original incarnation, the code points U+0900..U+0954 were a direct copy of the characters A0-F4 from the 1988 ISCII standard. The Bengali, Gurmukhi, Gujarati, Oriya, Tamil, Telugu, Kannada, and Malayalam blocks were similarly all based on their ISCII encodings.
The following Unicode-related documents record the purpose and process of defining specific characters in the Devanagari block:
Change the script of U+0970 DEVANAGARI ABBREVIATION SIGN to Devanagari for Unicode 6.0.
Make script extension changes in version 11.0 as documented in section 6B, pages 6-9 of L2/18-039.
Change the script property of U+0953 DEVANAGARI GRAVE ACCENT and U+0954 DEVANAGARI ACUTE ACCENT from "Devanagari" to "Inherited", for Unicode version 12.0.
Accept the twelve Indic characters with names and coding positions as documented in L2/01-431R