Practical limitations to media neutrality include the inability of journalists to report all available stories and facts, and the requirement that selected facts be linked into a coherent narrative. (Newton 1989) Since it is impossible to report everything, some bias is inevitable. Government influence, including overt and covert censorship, biases the media in some countries. Market forces that can result in a biased presentation include the ownership of the news source, the selection of staff, the preferences of an intended audience, or pressure from advertisers. Political affiliations arise from ideological positions of media owners and journalists. The space or air time available for reports, as well as deadlines needed to be met, can lead to incomplete and apparently biased stories.*
*-Not mine. Read Chomskys articles on media bias. It doesn't exist.