Part 3/7:
The challenger to pi is tau, defined as the ratio of a circle's circumference to its radius. The primary advantage of tau is that it provides a more direct relationship to the fundamental quality of a circle itself. Since one circumference is equal to two radii, using tau simplifies many aspects of trigonometry and circular calculations. According to the proponents of tau, defining tau as 1 is far more intuitive.
The proposal argues that using tau simplifies the learning process for students. For example, one full rotation around a circle would equal τ radians, making it instantly clearer. Quarter and half turns would then represent τ/4 and τ/2 respectively—convenient and straightforward as opposed to the convoluted relationships derived from pi.