Excerpts from SourceWatch
Propaganda shares many techniques with advertising or public relations; in fact, advertising and PR can be said to be propaganda promoting a commercial product. ... In a narrower and more common use of the term, propaganda refers to deliberately false or misleading information that supports a political cause or the interests of those in power.
The propagandist seeks to change the way people understand an issue or situation, for the purpose of changing their actions and expectations in ways that are desirable to the interest group. In this sense, propaganda serves as a corollary to censorship, in which the same purpose is achieved, not by filling people's heads with false information, but by preventing people from knowing true information.
What sets propaganda apart from other forms of advocacy is the willingness of the propagandist to change people's understanding through deception and confusion, rather than persuasion and understanding. The leaders of an organization know the information to be one sided or untrue but this may not be true for the rank and file members who help to disseminate the propaganda.
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In an even narrower, less commonly used but legitimate sense of the term, propaganda refers only to false information meant to reassure people who already believe. The assumption is that, if people believe something false, they will constantly be assailed by doubts. Since these doubts are unpleasant, people will be eager to have them extinguished, and are therefore receptive to the reassurances of those in power. For this reason propaganda is often addressed to people who are already sympathetic to the agenda.
Propaganda has sometimes been classified as "white," "black" or "gray."
- White propaganda generally comes from an openly identified source and is not intentionally deceptive.
- Black propaganda pretends to be from a friendly source, but is actually from an adversary and is intended to deceive its audience.
- Gray propaganda falls somewhere between white and black.