You may never have heard of modular arithmetic, but you use it every day without the slightest difficulty. In this system, numbers wrap around when they reach a certain size called the modulus; it is ...

I welcomed the New Year by playing mahjong with my family. The version we play starts with one person rolling three dice and then counting around the table of four players to whatever the total is.

With the advent of relatively large classes of students studying arithmetic in common schools, educators began to prepare special charts to assist in instruction. By 1900, these could be quite ...

Ancient Babylonian scribes learned to record numerical tables on clay tablets. If a schoolroom or library burned, the tablets baked hard, and might survive for millennia. Several such tablets are ...