f

F is the sixth letter of the Latin alphabet. In modern English it represents the voiceless labiodental fricative [f], as in “flower.” The uppercase form is F and the lowercase is f. Its name is pronounced “eff.”

Origin and form: The letter F entered the Latin alphabet through the Etruscans, who borrowed from the Greek writing tradition. Its form has remained largely stable since antiquity, and it has long been used to denote the same sound across many languages that adopt the Latin script.

Uses and symbols: In science and mathematics, F is used for several common concepts. In physics, F commonly denotes force in F = ma. In electrical units, the farad, the unit of capacitance, is symbolized by F. In chemistry, F is the symbol for fluorine, the element with atomic number 9. In thermometry, °F denotes degrees Fahrenheit. In astronomy, F-type stars are a spectral class. In mathematics, F often denotes a function or a family of functions.

Other uses: In music, F is a musical note and the key of F major. In everyday notation, F marks a failing grade in education, or a function in programming and computer science is often denoted by f. The letter also serves as an initial or shorthand in various fields.