Sometimes a pidgin language may develop. A pidgin language is a fusion of two languages that is mutually understandable for both speakers. Some pidgin languages develop into real languages (such as Papiamento in Curaçao or Singlish in Singapore) while others remain as slangs or jargons (such as Helsinki slang, which is more or less mutually intelligible both in Finnish and Swedish). In other cases, prolonged influence of languages on each other may have the effect of changing one or both to the point where it may be considered that a new language is born. For example, many linguists believe that the Occitan language and the Catalan language were formed because of a population speaking a single Occitano-Romance language was divided into political spheres of influence of France and Spain, respectively. Yiddish is a complex blend of Middle High German with Hebrew and borrowings from Slavic languages.