ÿ is a Latin script character composed of the letter Y and the diaeresis diacritical mark. It occurs in French as a variant of in a few proper nouns, as in the name of the Parisian suburb of L'Haÿ-les-Roses and in the surname of the house of Croÿ . It occurs in a few Hungarian names as well, such as Lajos Méhelÿ and Margit Danÿ. As rarely appears as the first letter in a name, and all-caps text typically omitted all accents, initially there was assumed to be no need for an uppercase when computer character sets such as CP437 and ISO 8859-1 were designed. However much software assumes that conversion from lower-case to upper-case and then back again is lossless, so was added to many character sets such as CP1252, ISO 8859-15, and Unicode (in which every pre-composed Latin character has both an upper- and lower-case version). This also happened to a more prominent character, the German ß. IPA uses [ÿ] as one of the Closed central compressed vowels, a type of vowel sound used in some spoken languages. In Unicode Letters with diaeresis Latin letters with diacritics Phonetic transcription symbols