The document discusses the history of magic squares. It states that the oldest known magic square is the Lo Shu, a 3x3 grid seen on a turtle's back by Emperor Yu in China over 4000 years ago. Each row, column and diagonal of numbers in a magic square adds up to the same sum, and the Lo Shu uses consecutive integers from 1 to 9. The document also provides instructions for building magic squares of odd numbers by placing the digits in order while moving up and to the right at each step.