U+03B6 "ζ" Greek Small Letter Zeta Unicode Character

U+03B6 "ζ" Greek Small Letter Zeta is the sixth letter of the Greek alphabet and represents the voiced alveolar fricative sound /z/ in Modern Greek, while in Ancient Greek it denoted the double consonant /zd/ or /dz/. It serves as the symbol for the Riemann zeta function in mathematics, a critical tool in number theory and analytic geometry, and is also used in physics to denote the damping ratio in mechanical and electrical systems. Derived from the Phoenician letter zayin, zeta is one of the earliest Greek letters with a linear form, and its lowercase shape has remained relatively stable in typography across centuries.