Political parallelism is a feature of media systems. In comparative media system research, it 'refers to the character of links between political actors and the media and more generally the extent to which media reflects political divisions.' Daniel C. Hallin and Mancini used the term to analyse links between media organizations and political tendencies; appropriating an older concept by Colin Seymour-Ure who had originally applied it in a narrower way to the links between the press and political parties. Political parallelism is a feature of media systems. In comparative media system research, it 'refers to the character of links between political actors and the media and more generally the extent to which media reflects political divisions.' Daniel C. Hallin and Mancini used the term to analyse links between media organizations and political tendencies; appropriating an older concept by Colin Seymour-Ure who had originally applied it in a narrower way to the links between the press and political parties. The term was defined in Daniel C. Hallin and Paolo Mancini’s Comparing Media Systems in 2004. The authors analysed media systems according to four dimensions: the development of a mass press, political parallelism, professionalization of journalists, and state intervention. According to these four dimensions, media systems were then categorised into three ideal models, the Polarized Pluralist Model, the Liberal Model and the Democratic Corporatist media system. There are five factors indicating a media system’s degree of political parallelism: In 2004, when Daniel C. Hallin and Paolo Mancini introduced the concept of political parallelism, they applied it to Western consolidated capitalist democracies. It refers to media content and the extent to which different media reflect distinct political orientations in their output. Historically, political advocacy was seen as an important function of the print media emerging in the late 18th to early 19th century. Political parties or other political actors established newspapers and supported them. The role of the journalist was to influence the public towards his or her political faction or cause, something which changed only in the 19th century when journalism norms moved towards the ideal of neutrality in reporting. Then, commercialization became an important force in the newspaper business. Papers no longer depended on patronage of political parties or actors, but adopted a more ‘balanced’ line. According to Jonathan Hardy newspapers could, by de-aligning themselves from politics and moving towards ‘objectivity’, 'reach an aggregated consumer audience that was not fractured along political lines. Overall, the economic rationale was that, with less bias, more readers would be attracted to a paper.' After the First World War, this changed again, when political conflict was reflected in the news and 'strong political polarization enhanced demand for overtly political papers.' However, the extent of this development differed in strength in different media systems. In 'Democratic Corporatist' media systems strong ties between the media and political institutions continued until the 1970s. In Polarized Pluralist systems, political parallelism in the press played a key role in the national development, for example in Spain and Italy. Even today, as Angelika W. Wyka argues about Italy and Greece, 'although the existing ethical codes are greatly thought to be a reflection of objective and impartial reporting, journalists tend to be somewhat, if not extremely, partisan.' In Central Eastern Europe, 'highly opinionated and politically-driven journalism also prevails.' As mentioned before, political parallelism is expressed in the partisanship of media audiences, too, when supporters of different parties buy different newspapers catering for their opinions and political preferences. In Germany, for instance, the daily newspaper Die Welt is seen as more conservative than the liberal Süddeutsche Zeitung, with die tageszeitung further to the left. In Spain, the newspaper El País had most readers among the voters of the Spanish Socialist Workers Party (PSOE), ABC is read widely among people voting for the People's Party (PP), and El Mundo predominantly by non-voters. Closely related to the concept of political parallelism is the distinction between internal and external pluralism. These two concepts refer to the media’s way of handling diversity in political loyalties and orientations. External pluralism is achieved at the level of the media system as a whole, when media outlets’ and organisations’ content reflect different points of views within society. Internal pluralism is achieved within one medium, when it attempts to report neutrally and balanced, and avoids affiliations with political groups. Media systems with a high degree of external pluralism will also have a high degree of political parallelism, whereas media systems with a high degree of internal pluralism will have a low level of political parallelism.