a) the northern branch led to the emerging of
Gupta (which existed in the Middle Ages), Nagari (later Devanagari), Sharada
(used by the Kashmiri language of the Dardic group), Nevari (used in Nepal),
Bengali, Oriya, Gujarati, Gurmukhi;
b) the southern branch resulted to several scripts in which modern Dravidian languages write (Kannada, Telugu, Malayalam etc.);
c) the south-eastern branch was popular in East Asia, Indochina and Malaysia, one of its modern descendants in the Singhalese script in Sri Lanka.
But though all these scripts differ somehow, the common Indian model of writing is the same and is clearly seen, for example, in the Devanagari script used in Hindi and Marathi: each symbol of the script sounds as a vowel or a combination of any consonant plus the vowel "a": ka, ga, jha etc. All the rest of vowels are added to consonantal symbols as diacritic signs over or under the symbol. Combinations of several consonants can modify symbols, and therefore actual Devanagari consists of about 600 different signs, while the basic alphabet includes just 49 letters.
Sometimes it is hard to see the phonetic association with the writing system: it is better seen in Southeast Asian scripts like Burmese and Thai, which also use Brahmi-type writing, and have to invent more additional dots and lines to reflect tones existing in their languages. But for Indo-European languages which invented Brahmi and then developed it into Devanagari, Bengali and other kinds of it, the system looks quite OK, and no attempts are noticed to turn Indian languages into the Roman alphabet users, as it is sometimes done in China or in Japan.
Languages which use Indic scripts:
Indic (a great lot of languages, including
Sanskrit, Hindi, Bengali, Marathi, Singhalese, Nepali, Gujarati), Dardic
(Kashmiri), non-Indo-European (Tibeto-Burmese, Dravidian, Munda, Sino-Tibetan,