First attested in the Kharoshthi and Brahmi inscriptions of ca. 250 b.c., the Indic family of scripts has proved one of the world's most successful. Originally devised for Middle Indo-Aryan, then adapted for the accurate notation of Sanskrit, the organizing principle is that of the alphasyllabary, in which consonants are voweled by the attachment of distinctive signs. The three main groups of Indic scripts derived from Brahmi in official use today illustrate progressively greater degrees of modification of the system, to write the modern Indo-Aryan languages, the Dravidian languages of south India, and the linguistically diverse languages of Southeast Asia.