Thomas Harriot
Harriot, Thomas
Born 1560 in Oxford; died July 2, 1621, in London. English mathematician.
In The Practice of Analytical Art (1631, published posthumously), Harriot introduced the signs > (greater than) and < (less than), used small letters to represent numbers, formulated equations based on this usage, found an expression for the area of spherical triangles, and did other important work.