A cedilla is a tail (¸) added under certain letters as a diacritic mark. The tail is a miniture cursive zs bottom half. The name "cedilla" is the diminutive[?] of the old Spanish name for zed, ceda. An obsolete spelling of "cedilla" is "cerilla" because the letters d and r were interchangeable in 16th-century Spanish.
The most frequent character with cedilla is the ç (c with cedilla). This letter was used for the sound of the affricate [ts] in old Spanish. Contemporary Spanish doesn't use it anymore since an orthographic reform in the 18th century.
C-cedilla was adopted for writing other languages, like French, Portuguese, Catalan, unofficial Basque, Occitan, and some Friulian[?] dialects, where it represents /s/ where "c" would normally represent /k/ (for example, normally pronouced as /ka/, ca pronouces as /sa/ if written as ça); or Turkish, Albanian, Azerbaijani, Tatar, Turkmen, Kurdish (at least the Mahabad dialect), and some Friulian[?] dialects, where it is used for the sound of the affricate [tS] (the same of English in church). It is also used in a Romanization of Arabic. (What are the represented letter and its pronunciation?)
And the s-cedilla, ş, represents /S/ (as in show) in Turkish, Azerbaijan, Tatar, Turkmen, and Kurdish. It is also used in some Romanizations of Arabic, Persian, and Pashto. (What are the represented letter and its pronunciation?)
In the Turkish alphabet both Ç and Ş are common letters, not a variant of C or S.
The most common English word taking a cedilla is probably "façade".
The Romanian Ș (ș) seemingly resembles the Turkish s cedilla, but it is actually a comma.
The diacritics on the Latvian letters g, k, l, n, and formerly r are considered by some to be cedillas and others to be commas.
Common misspelling and questions (FAQ)
edilla cdilla ceilla cedlla cedila cedila cedill ecdilla cdeilla ceidlla cedlila cedilla cedilal cedill ccedilla ceedilla ceddilla cediilla cedillla cedillla cedillaa dedilla xedilla fedilla fedilla vedilla c3dilla cwdilla csdilla c4dilla cddilla c4dilla crdilla cddilla ceeilla cesilla cexilla cerilla cecilla cerilla cefilla cecilla ced8lla cedulla cedjlla ced9lla cedklla ced9lla cedolla cedklla cediola cedikla cedi,la cedipla cedi.la cedipla cedi;la cedi.la cediloa cedilka cedil,a cedilpa cedil.a cedilpa cedil;a cedil.a cedillq cedillw cedillz cedillw cedills cedillz cedylla cedillasa reprieve, he turned to Julian Romero, and asked him once more if there looked on the ground, and was silent. He then closely clenched his teeth, threw off his mantle and robe, knelt presented him the crucifix to kiss, and administered to him extreme silk cap over his eyes, and awaited the stroke. Over the corpse and the fall on every heart. Loud sobs alone broke the appalling silence. The wiped his eyes as his victim died. Shortly afterwards Count Horn advanced on the scaffold. Of a more for hatred against the king, he had received the sentence with less forth in bitter reproaches against the king, and the bishop with than to abuse them in imprecations on his enemies. At last, however, he first he was disposed to refuse. He mounted the scaffold with the same attendants as his friend. In Egmont's, free, and he was dressed in a black doublet and cloak, with a cast his eyes upon the corpse, which lay under the cloth, and asked one in the affirmative, he said some words in Spanish, threw his cloak from fatal blow. The heads of both were fixed upon the poles which were set up on the they were taken down, and, with the two bodies, placed in leaden coffins scaffold, the citizens of Brussels would not be prevented from dipping .