The Binet formula is a mathematical expression used to calculate the nth term of the Fibonacci sequence directly, without needing to compute all previous terms. It is given by the formula: F(n) = \frac\phi^n - (1 - \phi)^n\sqrt{5} , where \phi (phi) is the golden ratio, approximately 1.618. This formula was named after the French mathematician Jacques Philippe Marie Binet, who introduced it in the 19th century. The Fibonacci sequence starts with 0 and 1, and each subsequent number is the sum of the two preceding ones, making it a fundamental concept in mathematics and nature.