Bavarian (Bairisch ˈbaɪʁɪʃ), or alternately Austro-Bavarian, is a West Germanic language consisting of a group of dialects, part of the Upper German family, together with Alemannic and East Franconian. Bavarian is spoken by approximately 12 million people in an area of around , making it the largest of all German dialects. It can be found in the German state of Bavaria (especially Old Bavaria), most of the Republic of Austria (excluding Vorarlberg) and the Italian region of South Tyrol. In 2008, 45 percent of Bavarians claimed to use only dialect in everyday communication. Prior to 1945, Bavarian was also prevalent in parts of the southern Sudetenland and western Hungary. Bavarian is commonly considered to be a dialect of German, but some sources classify it as a separate language: the International Organization for Standardization has assigned a unique ISO 639-3 language code (bar), and the UNESCO lists Bavarian in the Atlas of the World's Languages in Danger since 2009; however, the classification of Bavarian as an individual language has been criticized by some scholars of Bavarian. Reasons why Bavarian can be viewed as a dialect of German include the perception of its speakers, the lack of standardization, the traditional use of Standard German as a roofing language, the relative closeness to German which does not justify Bavarian to be viewed as an abstand language, or the fact that no country applied for Bavarian to be entered into the European Charter for Regional or Minority Languages. The difference between Bavarian and Standard German is larger than the difference between Danish and Norwegian or between Czech and Slovak. The word Bavarian is derived from the name of the people who settled Bavaria along with their tribal dialect. The origin of the word is disputed. The most common theory traces the word to Bajowarjōz, meaning "inhabitants of Bojer land". In turn, Bojer (Boii, Boier) originated as the name for former Celtic inhabitants of the area, with the name passing to the mixed population of Celts, Romans, and successive waves of German arrivals during the early medieval period.