Who was the mathematician known for his work with logarithms and exponents?

John Napier was the mathematician known for his work with logarithms and exponents.

Napier was a Scottish mathematician, astronomer, and landowner who lived from 1550 to 1617. His 1614 book, Mirifici Logarithmorum Canonis Descriptio, introduced logarithmic tables that made difficult multiplication, division, and power calculations much faster. This was especially valuable in astronomy, navigation, and surveying, where calculations with very large or very small numbers were common.

A logarithm reverses exponentiation: it tells you which exponent produces a given number. For example, log10(1,000) = 3 because 10³ = 1,000. Napier’s original logarithms were not exactly the common base-10 logarithms used in many classrooms today. Henry Briggs later worked with Napier to create more convenient base-10 tables.

Napier also invented Napier’s bones, a set of numbered rods that helped users perform multiplication and division by hand. He is sometimes described as inventing exponents themselves, but his best-known contribution was making logarithmic calculation practical and widespread.