Zeta (capital ζ, lowercase ζ) is the sixth Greek letter.

There are many functions called Zeta functions in mathematics, the most famous of which is Riemann zeta function.

The z of the Latin letter is changed from Zeta.

Greek alphabet

Because the writing tool in Greece is a wax board, sometimes the first line is written from right to left and then from left to right, which becomes the so-called "cultivated land" writing, and then gradually evolves into all writing from left to right. The direction of the letters is also reversed. The Romans introduced the Greek alphabet, changed it into Latin alphabet with a little change, and it became popular all over the world.

Greek letters are widely used in academic fields, such as mathematics. Cyrillic letters also evolved from Greek letters. The English word alphabet (letter) comes from the alphabetum in vulgar Latin, and the alphabetum comes from the Greek word α λ φ α β ο ν (transliteration of Beton), which is the synthesis of the first two Greek letters α(Alpha) and β(Beta).