Hard and soft C

In the Latin-based orthographies of many European languages (including English), a distinction between hard and soft ⟨c⟩ occurs in which ⟨c⟩ represents two distinct phonemes. The sound of a hard ⟨c⟩ (which often precedes the non-front vowels ⟨a⟩, ⟨o⟩ and ⟨u⟩) is that of the voiceless velar stop, [k] (as in car) while the sound of a soft ⟨c⟩ (typically before ⟨e⟩, ⟨i⟩ and ⟨y⟩), depending on language, may be a fricative or affricate. In English, the sound of soft ⟨c⟩ is /s/ (as in "citrus").

There was no soft ⟨c⟩ in classical Latin, where it was always pronounced as /k/. Modern English pronunciation of early Latin often uses /s/ instead, as with Caesar "KYE-sahr" becoming "SEE-zer".

This alternation has its origins in a historical palatalization of /k/ which took place in Late Latin, and led to a change in the pronunciation of the sound [k] before the front vowels [e] and [i]. Later, other languages not descended from Latin, such as English, inherited this feature as an orthographic convention.

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