Greekletter

Greekletter refers to the set of 24 letters of the Greek alphabet and to the symbols derived from those letters that are widely used in writing, science, and scholarship. The term is also encountered in contexts such as naming fraternities and sororities that use Greek-letter combinations to designate their organizations. The alphabet’s letters have both uppercase and lowercase forms and are used as symbols beyond their original phonetic values.

The Greek alphabet originated in ancient Greece around the 8th century BCE, evolving from the Phoenician script. It provided a standardized set of characters with names such as alpha, beta, gamma, delta, and so on. In modern usage, Greek letters retain distinct names and are commonly written in both cases, with a special note for sigma, which has two lowercase forms: σ and ς (the latter used at word endings). The system also incorporates diacritical marks in historical and polytonic contexts, though modern monotonic Greek uses a simplified orthography.

In mathematics and the sciences, Greek letters function primarily as symbolic representations rather than phonetic signs. Lowercase Greek letters such as alpha, beta, theta, lambda, mu, pi, and sigma are often used for variables, angles, and coefficients or for special functions, while uppercase letters like Delta, Sigma, Pi, and Gamma denote constants, sums, products, or set names. Greek letters also appear in astronomy to designate stars within a constellation (e.g., Alpha Centauri), though this practice has many exceptions and variations. In statistics, Greek letters commonly denote population parameters (mu, sigma) or significance levels (alpha).

Encoding and typography have integrated Greek letters into digital text. They appear in Unicode blocks dedicated to Greek, and the shapes have influenced the development of the Latin alphabet. Greek-letter organizations in universities continue to use Greek combinations to name and identify groups.