Block from U+0900 to U+097F. This block was introduced in Unicode version 1.1 (1993). It contains 128 codepoints.
The Wikipedia provides the following information on block Devanagari:
Devanagari is a Unicode block containing characters for writing Hindi, Marathi, Sindhi, Nepali and Sanskrit. 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.