According to historians Mathematicians are using Greek letters world wide since 18th century because they made it easier to distinguish mathematical symbols from the surrounding text. Some of the Greek letters used in mathematics have their own backstory: π (Archimedes' constant) is the first letter in περιφέρεια (periphereia) and περίμετρον (perimetron), which both means circumference, φ (the golden ratio) is the initial of Phidias (Φειδίας) who decorated the Parthenon, a building that illustra