Despite the relative dominance of the 26-letter English alphabet, Greek letters continue to exist and influence today's society. For example, a dominant man or dog is often known as the "alpha male" or "alpha dog." (The less-dominant might be the "beta.") Fraternities and sororities are almost exclusively named for a series of Greek letters, a holdover from the days when elite colleges routinely instructed students in Latin and Greek and thus Greek letters made the fraternity sound more exclusive.

Science and math are full of Greek influence, such as the number 3.14, known as "pi" or Π. "Gamma," used to describe rays or radiation, and "psi," (pronounced "sy"), used in quantum mechanics to denote wave function, are just a couple of the many ways science intersects with the Greek alphabet. And software developers might speak of "beta-testing" something, meaning the product is given to a small group of end-users to try out. Greek letters have been used to represent numbers since antiquity. Aristotle used them, for example, and the custom continued throughout history. (As we said earlier, Greek is the oldest European language.)

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