Vedic mathematics is a unique system of mental calculations based on 16 sutras or formulas derived from Vedic texts. It allows calculations like multiplication, division, square roots, and more to be done very quickly in the head. Some key sutras include Ekadhikena Purvena for squaring numbers ending in 5, Nikhilam Navatashcaramam Dashatah for multiplying numbers near multiples of 10, and Urdhva Tiryagbhyam for general multiplication using a vertical and diagonal approach. Vedic maths aims to reduce the usual effort and time of calculations through ingenious principles like proportionality, symmetry, and approximation.