San (letter) San (letter) San (Ϻ) was an archaic letter of the Greek alphabet. Its shape was similar to modern M, or ϡ, or to a modern Greek Sigma (Σ) turned sideways, and it was used as an alternative to Sigma to denote the sound . Unlike Sigma, whose position in the alphabet is between Rho and Tau, San appeared between Pi and Qoppa in alphabetic order. In addition to denoting this separate archaic character, the name "San" was also used as an alternative name to denote the standard letter Sigma. The existence of the two competing letters Sigma and San is
Greek alphabet parallel to the practice in Latin and other western languages. The Greek alphabet was the model for various others: It is also considered a possible ancestor of the Armenian alphabet, which in turn influenced the development of the Georgian alphabet. Apart from the daughter alphabets listed above, which were adapted from Greek but developed into separate writing systems, the Greek alphabet has also been adopted at various times and in various places to write other languages. For some of them, additional letters were introduced. Greek symbols are used as symbols in mathematics, physics and other sciences. Many symbols have traditional