Adam Ries (1492–1559) was the first to write several books teaching the arithmetic method by the old abacus and new Indian methods; his books also presented the basics of addition, subtraction, multiplication, and division. Unlike most books of his time that were written in Latin and only understood by mathematicians, scientists, and engineers, Ries’s books were written in his native German and were therefore understood by the general public. The books were also printed, making them more readily available to a wider audience.