C

In physics, symbol for coulomb, the SI unit of electrical charge.

C

In computing, a high-level, general-purpose programming language popular on minicomputers and microcomputers. Developed in the early 1970s from an earlier language called BCPL, C was first used as the language of the operating system Unix, though it has since become widespread beyond Unix. The original language has evolved many derivative variants, including the popular C++ and C# versions. It is useful for writing fast and efficient systems programs, such as operating systems (which control the operations of the computer).

C

Abbreviation for centum (Latin ‘hundred’); century; centigrade; Celsius.

C

Third letter of the English alphabet. It corresponds to Hebrew gimel and Greek gamma (Γ, γ), both derived from the Semitic word for ‘camel’. Originally representing a hard /g/, it was also used by the Romans for /k/. In English it can have the sound of the unvoiced alveolar fricative /s/, as in ‘face’, or the unvoiced velar plosive /k/, as in ‘cat’.

These sounds can also be spelt s and k respectively. When followed by an h, c usually denotes an unvoiced palatoalveolar affricate, as in ‘church’, but can also represent the sounds in ‘machine’ and ‘chorus’. In Welsh, ch denotes an unvoiced velar or uvular fricative.

Etruscan did not distinguish between /k/ and /g/, and used the letter c for both. The Latin alphabet adopted from Etruscan three signs with the sound /k/; c, k, and q. It later dropped the k, and used c for both /k/ and /g/. The letter q, when followed by u, was used for the sound /k/. They created a new letter 312 BC for the sound /g/, retaining the letter c for the sound /k/.

C

In music, the keynote, or tonic, of the scale of C major.