India was home to one of the world’s earliest civilizations, the Indus River Valley civilization that flourished between 3300 and 1300 BCE. The system of writing developed there remains undeciphered. Today, India encompasses dozens of writing systems and hundreds of languages and dialects. One of India’s 20 official languages is Hindi, a member of the Indo-European language family. In Hindi, the words for numbers up to ninety-nine are irregular, a trait thought to impose a significant demand on human memory. Typically, irregularity is confined to the lower numbers, with the smallest, one to about three or four, always being the most irregular as a consequence of the way the first words for numbers emerge in any language. In its unusual irregularity, Hindi is contrasted with Mandarin Chinese, a language whose numbers are profoundly regular. Regularity provides a transparency thought to aid the learning and acquisition of words for numbers. Some of the region’s languages count by twelves rather than tens, creating duodecimal systems of numbers. Examples include Sora and Chepang, languages that are unrelated to one another. Sora numbers additionally involve a vigesimal base.