The Spanish diacritic is a mark used to modify the sound of a letter in the Spanish language. The two most common diacritics are the tilde (5 letters) and the cedilla (7 letters). The tilde is a small wavy line placed over a letter, usually an 'n' or 'a', to indicate a nasal sound. The cedilla is a small hook placed under the letter 'c' to indicate a soft 's' sound. Both of these diacritics are used to differentiate between words that would otherwise be spelled the same.